Charlatans, Neurotics, And Scheisters: A Daubertospective View Of Science In The Courtroom For The Environmentally Challenged

Carl H. Johnson, University of Minnesota Law School
1999 First Place Winner


The “experts” have a penchant for being wrong, particularly when it comes to novel scientific theories. Less than six years ago, one scientist opined that “research during the last five years has demonstrated that cloning mammals (including humans) is theoretically impossible with today’s technology – and with any technology realistically in sight.” [1] In February of 1997, that scientist was proven wrong when Dr. Ian Wilmut, a Scottish embryologist, announced the birth of a sheep named Dolly, a clone of another sheep.[2] Scientific experts in the late nineteenth century considered mechanized flight and missions to the moon mere science fiction. As we progressed through our elementary education, teachers told us that long ago people believed that the world was flat. We are constantly reminded that science is not a bastion of certainty and objectivity,[3] but a discipline that “progresses by hunch, vision, and intuition.”[4] More often than not with science, the lines between fact and theory, discovery and invention, are blurred and indistinct.[5]

Unfortunately, the lack of certainty is not the only weakness that science bares for the world to see. “True science,” as touted by those who object to novel scientific theory,[6] also has a history of being used as a political tool. For centuries, the cranial measurements of Blacks and Indians were used to “prove” they were more closely related to gorillas and orangutans than to human beings, conveniently justifying slavery and genocide.[7] During World War II, the sciences of anthropology, psychiatry, and clinical psychology joined forces to aid the United States government in justifying a military and propaganda war against the Japanese.[8] Today, special interest groups are believed to use their financial clout to attack and intimidate scientists and institutions that engage in research unfavorable to industry.[9] And recently, Congress attempted to enact legislation that would silence any discussion by the EPA or the Clinton Administration on the effects or existence of global warming.[10] Time and time again, science shows us that objectivity is more fantasy than reality.

The subjective and political problems associated with “scientific knowledge” come to a head in courtroom battles over Multiple Chemical Sensitivity, or MCS. MCS is a “chronic multisystem disorder, usually polysumptomatic, caused by adverse reactions to environmental incitants, modified by individual susceptibility and specific adaptation.”[11] Put more simply, it is a multi-symptomatic disorder affecting multiple organ systems resulting from exposure to a multitude of chemicals at levels tolerated by the majority of the population.[12] Despite thousands of people being affected by this disorder,[13] mainstream medical and scientific organizations claim it does not exist.[14] The vast majority of practitioners who treat MCS are “clinical ecologists,” a variety of physicians who have medical and scientific backgrounds. The methodologies of clinical ecologists[15] are derided as untraditional and unreliable. Throughout the entire scientific debate, it becomes evident that the scientific community’s rejection of MCS and clinical ecology goes beyond mere methodology, but can be more readily attributed to a selective bias against MCS and a political agenda to keep it out of the courtroom.[16]

Despite its problems, science is an invaluable tool for the toxic tort plaintiff in the courtroom.[17] Unfortunately, the uncertain and subjective nature of science can create complications for its use in the courtroom. Therefore, the opponents and proponents of scientific evidence need to be cautious. There is ample potential for abuse by both sides, the plaintiffs and defendants, regarding admission of expert testimony. Plaintiffs may use “junk science”[18] to promote a tentative claim while defendants may try to bury legitimate scientific evidence to protect industry from the costs of using chemical substances in the modern world. While for most of this century the Frye[19] rule governed such matters in federal courts, the Supreme Court has more recently changed the equation with the Daubert[20] andJoiner[21] cases.[22]

At first glance, application of Daubert seems to be overly prejudicial to plaintiffs. In the vast majority of toxic tort or products liability cases post-Daubert and post-Joiner, plaintiffs have failed to convince the court to admit vital expert testimony.[23] This is especially true in MCS cases, where the plaintiff attempts to prove that exposure to the defendant’s chemicals or product triggered the onset of MCS symptoms.[24] A closer examination reveals, however, that in many of the cases where the plaintiff’s expert was denied admission, the selection of the experts themselves was the cause for losing the Daubert argument.[25] MCS cases are an exception to this rule.[26]

This paper seeks to provide guidance on the more subtle issues associated with the Daubert and Joiner cases. One of the primary difficulties associated with the admission of scientific expert testimony is the vastly different lenses through which scientists and lawyers see the world. Both cultures differ on what constitutes “proof” and, consequently, who should be considered an “expert.” Section II compares the scientific method with legal deductive methods of evidentiary proof, concluding with examples of how these differences have raised sharp criticism by scientists over the use of expert testimony in the courtroom.

Section III introduces Daubert and Joiner and offers a point-by-point discussion of how toxic tort claimants have fared in the wake of Daubert and Joiner. Section IV provides specific examples of what has caused plaintiffs to fail or succeed.

Section V introduces the controversy surrounding MCS, with a focus on the scientific community’s criticism of the syndrome and clinical ecologists, and how MCS plaintiffs have fared in the federal courtroom. Section VI explores how a plaintiff might successfully bring novel scientific evidence into the courtroom, focusing on the issues and challenges associated with MCS.

This paper concludes that while the application of Daubert and Joiner has answered many of the criticisms over the use of scientific experts in the courtroom, it also has the potential for abuse as a backdoor application of the Fryestandard regarding novel scientific theories. There is a way that plaintiffs seeking to introduce novel scientific expert testimony under Daubert can be successful, they merely need to draw the court’s attention away from general acceptance and back to the Daubert emphasis on the scientific method. This paper will address these concerns and show how an open door is not a prelude to a flood.


A. The Scientific and Legal Cultural Clash

No practitioner would deny that a cultural disparity has developed between lawyers and scientists over the last century. Steven Goldberg identified one key difference between the two professions when he stated that the “scientists’ emphasis on progress is replaced by the lawyers’ emphasis on process.”[27] The Supreme Court has even recognized the “important differences between the quest for truth in the courtroom and the quest for truth in the laboratory.”[28]

Despite the differences in culture, science and law not only share many similarities, they also are both integral to a functioning modern society. Both disciplines share in a belief that behavior must be rule or law-driven.[29] Both seek to justify their authority through claims of establishing rational, objective knowledge. Through the process of finding the truth, whether it is scientific or legal, both professions engage in an adversarial process.[30] Both develop specialized disciplines grounded in procedures, skills, attitudes, and values unique to the sub-discipline.

There is a very simple explanation for this love-hate relationship. Both professions employ divergent methodologies and processes designed to find the “truth.” A scientific expert presenting an opinion based on “hard” science[31] may hold in contempt another expert whose opinion is merely based upon a legal standard of proof,[32] lacking in the formalities and rigors of the scientific method. Hence the ability to understand what it means to be an expert in each field lies in the methodologies employed.

B. Scientific Proof Through Process and Method – The Expert as Master

A scientist yearns to seek the knowable and constant rules of the universe.[33] The scientific expert is the individual who has meticulously applied the scientific method to theory, tested that theory, and consistently gained respect for adherence to procedure and acceptable methodology. For purposes of this discussion, the “scientific expert” is the scientist in the laboratory, as opposed to the “legal expert,” who is the scientist in the courtroom. This scientific expert has pursued such endeavors in a “legitimate” field of science and has been accepted by fields of specialty other than her own.[34] In other words, “science” is what a majority of scientists say it is.[35] The “expert” in the scientific sense is the master of that science.

At the origin of this success lies the valid scientific theory. Karl Popper stated that a truly scientific theory was identified not by its verifiability but its falsifiability.[36] Each theory that comes to the fore is not necessarily new, but built upon the work that has come before it.[37] Some of these theories can also be viewed as paradigms. Paradigms, such as Newtonian physics or Ptolemaic astronomy, are sufficiently unique to attract a group of scientists away from competing modes of scientific activity yet open-ended enough to leave a variety of puzzles for the new group of scientists to resolve.[38] A paradigm is what members of a particular scientific community share and, conversely, a scientific community is a group that shares a particular paradigm.[39] These new paradigms are only successful if they are more capable of solving acute problems than their competitors.[40] As they emerge, these new theories sometimes require such widespread reevaluation of accepted science as to leave the vast hoards of the scientific community in a state of “profound professional insecurity.”[41] These new theories emerge, in great part, because the old rules no longer apply.[42]

In order for a theory to survive beyond its infancy, it must be proven, or deemed “valid.”[43] There are several generally accepted principles that lie at the heart of a valid theory. Traditionally the criteria of internal consistency, explanation, prediction, and control have been considered vital elements of a valid theory.[44] Internal consistency is essentially the absence of self-contradiction. Without consistency in the theory, it cannot be tested. Therefore, the internal consistency of the theory is the foundation on which validity can be built.[45] While all theories must be internally consistent, the degrees of explanation, prediction, and control will vary.[46]

Popper’s process of falsification also incorporated some of these points, listing a variety of ways in which a theory could be tested:


(1) by comparing the conclusions that can be deduced from the theory among themselves, to see whether they are internally consistent;
(2) by investigating the logical form of the theory, to determine “whether it has the character of an empirical or scientific theory, or whether it is, for example, tautological;”
(3) by comparing the theory with other theories, “with the aim of determining whether the theory would constitute a scientific advance should it survive our various tests;” and
(4) by “testing of the theory by way of empirical applications of the conclusions which can be derived from it.”[47]

Great advances or new paradigms are not made through theory alone, but through testability, or falsifiability. The problem of validating or invalidating scientific theories lies at the heart of the scientific process.

Just as many lawyers feel that the judicial process of establishing legal “proof” is far from objective,[48] so do scientists feel about the “scientific method.”[49] Karl Popper insisted that there could be no simple “scientific method” that applied to all disciplines.[50] Richard Yeo suggests that in the rhetoric surrounding assumptions about science, the scientific method was seen in “the social relations of science” as accessible, single and transferable.[51] It therefore seems that scientists can agree to disagree on the exact methodologies to apply to science, depending on what type of science is being studied.

Despite the lack of uniformity in specific methods, there are essential core elements that comprise the scientific process. First, a theory is derived through induction from observations of the real world, or from previous theories and data from studies.[52] Next, specific predictions are derived from the theory by a logical process of deduction.[53]Then, the scientist obtains relevant data to test the theory by using some methodology in the investigation of the real world.[54] It is with the application of this methodology that the differences arise among disciplines. Finally, the data are tested against the predictions of the theory, resulting in support, refutation, or alteration of the original theory.[55]

Taking these essential core functions of the scientific process, the scientist must design a methodology that will legitimately test and eventually prove or disprove the theory. At the heart of all scientific methodologies is the simple premise that the scientist develops a hypothesis and then tests the hypothesis through experimentation.[56] The important way in which these distinct methodologies differ is in their treatment of variables that are encountered in the course of the investigation.[57] A variable in the scientific sense is a deviation or aberration when compared to what is expected.[58] A scientist can address variables through manipulation, measurement, keeping them constant, randomizing them out, or simply ignoring them.[59]

Scientists also employ statistical methodology in order to verify or support the base methodology used to test the theory. Courts have accepted the importance of statistical sampling, but recognize its validity only if the sample is unbiased and representative.[60] Statistics is not only a process of measurement, lending the results to empirical analysis, but an end itself. The validity of statistical technique serves a dual purpose as both the methodology by which a scientist can verify conclusions and the conclusion that must be validated.[61]

The Scientific Process in Focus: A Close Look at Epidemiology and Toxicology

Epidemiology has been defined as “the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems.”[62] It compares control groups of unexposed individuals to groups of individuals exposed to a potential cause of a disease in order to determine if the exposed individuals bear a greater risk of contracting the disease.[63] Epidemiological studies seek to find statisticalassociations between exposure to an agent and the occurrence of disease.[64] They focus on the general causation of a disease rather than on individual cases, or specific causation.[65] Epidemiology is universally considered to be the best scientific means for proving causation in the courtroom.[66]

There are several types of epidemiological studies. Cohort studies, also known as “follow-up” or “incidence” studies, begin with a group of individuals who are free of a disease and are classified into subgroups according to exposure to a potential cause of the disease.[67] Starting with the population at large, a group of people without the disease is broken up into two groups, one exposed, one not exposed. Each of these two groups is then broken up into groups of people who have the disease and those who do not.[68] These groups are studied over a long period of time and the incidence of disease are calculated and compared.[69] The cohort study is considered the best means of determining causation of a disease and for assessing the potential rate of occurrence for a disease.[70] Epidemiological evidence is not, however, required before a hypothesis is considered valid scientific evidence.[71]

The other most common form of study used by epidemiologists is the “case control study.”[72] Widely used because of their simplicity and economic advantages, case control studies include people with a disease and a control group of people unaffected by the disease.[73] The researcher then compares past exposures and experiences between members of the two groups.[74] Typically case-control studies should include study groups that have recently manifested illness in order to avoid the difficulty of isolating the factors that may have contributed to causation in the disease.[75] Based on these comparisons, the researcher will create a “relative risk ratio.”[76] A case-control study can also be carried out prospectively in order to collect exposure data before the development of the disease. Such a study is called a “nested case-control study.”[77] Case studies are considered to employ valid scientific methodology, yet still suffer from some methodological flaws.[78]

Another valuable tool in discerning the cause of an illness is toxicology. Toxicology is “the study of the adverse effects of chemical agents on biological systems.”[79] It is considered by some to be a fairly “new” science, yet the observation of harmful effects of substances on humans predates history.[80] While many sub-disciplines of toxicology exist, the form most relevant to this discussion is “clinical toxicology,” which is a branch of medical science that studies poisoning from xenobiotic[81] sources and the chemical means for counteracting the effects from these chemical or natural sources.[82]

There are three basic tenets of toxicology: (1) all chemicals have the potential to be harmful given the right dosage; (2) many chemical agents have a signature pattern of toxic effects that are used to establish causation; and (3) responses in laboratory animals are useful in determining the potential effects on humans.[83] Toxicology in general seeks to identify what chemicals pose a threat to human populations and the risks associated with a chemical exposure at a given dose.[84] Unlike epidemiology, which seeks primarily to establish causation, toxicology seeks primarily to estimate the given risks associated with potential exposure.

Often based on animal experiments, toxicological evidence in the courtroom seeks to establish dose-response relationships, extrapolating data from animals to humans.[85] This extrapolation takes two steps: from animals to humans and from high doses to low doses.[86] Typically, animals receive brief, severely high doses and humans receive lower-level exposures over long periods of time. There cannot, however, be a direct extrapolation without a corresponding human study; otherwise, there is great potential for a significantly high error rate.[87] Dose-response relationships also consider the intensity of the exposure, the age of the exposure, and any other factors that might affect response, such as lifestyle.[88] They seek to estimate the dose required to place a population at risk and determine the concentration of a chemical to which humans are likely to be exposed.[89]

The World Health Organization, the National Academy of Sciences and numerous United States government agencies have adopted a set methodology for determining the possible effects of a toxin on individuals.[90] First, an evaluation is made of the chemicals to which the individual might have been exposed, and of the concentrations of these chemicals in air breathed by the individual. The second step involves an evaluation, based on the published scientific literature, of the exposures necessary to produce the adverse effects associated with the chemicals to which individuals may be exposed.

Finally, these two evaluations are then combined in the final step of the risk assessment to provide an estimate of the likelihood that any of the harmful properties of any or all of the chemicals might have been expressed in the exposed individual.[91] A simple process of toxicological proof regarding causation would include the following: experimental evidence, the ability to replicate experimental results, and a reasonable mechanism to explain the effect.[92]

The problems associated with toxicology are well-documented and lamented.[93] Standing alone, toxicological data may meet with stricter scrutiny in the courtroom. In conjunction with epidemiological data, however, toxicological data is more useful. The symbiotic relationship between these two fields of expertise is well known.[94]

The interaction between these two disciplines, that is, understanding the questions they seek to answer, is a vital foundation for understanding the perspective of the scientific expert on the issue of causation. The cause of a disease is considered to be “an event, condition, characteristic” or combination of these factors that play a role in producing the disease.[95] A cause is considered “sufficient” when it produces or initiates a disease and is considered “necessary” if a disease cannot develop without it.[96]

More often than not, a sufficient cause is a combination of several factors. These factors lead to an increased susceptibility to a disease that, when combined with exposure to a contaminant, will produce the physiological response that precipitates the disease.[97] The four major factors that contribute to the causation of a disease are (1) predisposing factors, such as age, genetics, and previous illness; (2) enabling factors, such as poor nutrition and insufficient medical care; (3) precipitating factors, such as exposure to a specific disease agent; and (4) reinforcing factors, such as repeated exposure or unduly hard work.[98]

The process of determining whether observed associations among factors are likely to be causal is called a causal inference.[99] Before a causality can be established, other factors or “variables”[100] – such as bias,[101] chance or confounding – must be eliminated.[102] This process of elimination involves established criteria for determining causation by objectively testable means.

The investigating scientist must follow certain criteria in order to prove causation. In epidemiology, this involves a temporal relation, plausibility, consistency, strength of association, a noticeable dose-response relationship, and a study design to test these factors. The temporal relation is very crucial; the cause must precede the effect. The potential explanation for causation is plausible if it is consistent with other knowledge. Consistency is shown when several studies produce the same result. A strong association is demonstrated through the relative risk ratio.[103]Then, the scientist determines the dose-response relationship through measuring the change in level of a possible cause and linking those changes to the prevalence of an effect. If the removal of a possible cause results in a reduction in disease risk, a likelihood of a causal relationship is strengthened. Only a well-designed study will produce reliable results.[104] Finally, the expert must judge the evidence, and make a determination as to whether or not the evidence points to the perceived cause.[105]

The validity of the theory, adherence to methodology, and dedication to process are all means by which the scientific community judges its own experts in the laboratory. In the courtroom, however, the legal expert is merely one tool to be used in proving injury or illness causation. In the courtroom, the expert is judged by an entirely different set of rules.

E. Legal Proof Through Induction and Persuasion – The Expert as a Tool

A legal belief that leads to a decision – unlike a scientific one – is often beyond objective testability.[106] The law also rarely strives to concentrate solely on factual truth, seeking instead to understand a more general truth.[107] In the courtroom, the expert is not the individual seeking truth, like the scientific “master,” but a tool in that search for truth; and merely one piece in the inductive puzzle.[108] While a scientist may use relative risk ratios as persuasion, a lawyer uses the weight of evidence, sometimes consisting of expert testimony, to persuade by mere argument that the truth, if it is out there, is what the lawyer says it is. While this principle may seem disconcerting to the strictly methodological scientist, it is not the free-for all system that some claim it is.

Lawyers use a variety of time-tested methods to determine the “truth” in a litigious proceeding. There are required and standard procedures for examining witnesses, introducing exhibits, and making arguments.[109] There are rules of procedure and evidence at both the state and federal level that govern the methodologies that lawyers use in the courtroom to prove causation through the use of physical evidence, eyewitnesses, expert testimony, and other means at the lawyer’s disposal. Within the guidelines of these rules regarding legal methodology, lawyers also follow certain steps to establish causation through the process of logical inference. In fact, these procedures sometimes generate skeptical pressure on “established science.”[110]

Lawyers must adhere to specific standards in proving causation in the courtroom. Depending on the jurisdiction and the type of case, a lawyer must prove one of three types of causation.[111] First, alleged wrongful or negligent behavior must be the cause-in-fact of the harm. This is also known as the sine qua non rule or “but-for” causation.[112] To prove cause-in-fact, a plaintiff’s attorney must show that the defendant’s conduct directly caused the injury sustained by the plaintiff.[113] A defendant can defeat cause-in-fact evidence by showing that the plaintiff suffered the injury in question prior to the occurrence of the defendant’s alleged wrongful conduct.[114]

More often than not, particularly in toxic tort cases, there is a long and tenuous chain between the defendant=s actions and the plaintiff’s injuries, forcing the plaintiff’s lawyer to prove “proximate” causation.[115] Under the theory of proximate cause, liability is determined based on a plausible, causal connection with the negligent act and subsequent injury. The rules of proximate or legal cause limit the defendant’s liability to persons and consequences that bear some reasonable relationships to the defendant’s alleged tortious conduct. Whether and how proximate cause rules shall be applied is a question of law for the court.

Proximate cause presents two problems of proving a connection between the defendant’s action and the plaintiff’s injury. The first problem is one of “remoteness,” that is, the actual harm is either unpredictable with a long chain of intervening causes or an unlikely event or one with a severely low probability. The second problem involves some intervening event or action that breaks the chain of causation; an intervening event that may relieve the defendant of liability.[116]

A third notion of causation, known as probabilistic causation, incorporates probabilistic reasoning as opposed to the causal chains involved in proximate causation.[117] Given the complexity of the issues associated with toxic torts, the new theories, and the frontier science involved, the simple model of showing “yes or no” that a single act definitely did or did not cause an injury is difficult to apply. Thus, statistical evidence is required to estimate the defendant’s contribution to the plaintiff’s injury.[118]

In the process of showing causation, the plaintiff in a tort case bears the burden of proving injury through production of evidence and persuasion on the weight of that evidence. A plaintiff must meet the burden of production by bringing forth factual evidence to support each element of the claim. The plaintiff also has a burden of persuasion, meaning that he must convince the jury the his version of events or elements in the chain of causation is “worthy of their collective belief with a minimum level of certainty.”[119] The three most common standards of persuasion used in civil cases are: (1) “by a clear and convincing evidence,”[120] (2) “more likely than not,”[121] and (3) “by preponderance of the evidence,”[122] which is used primarily in toxic tort, products liability, and occupational disease cases.[123] Confusion and misunderstanding are exacerbated when the standards of proof differ dependent upon the type of law at question. For example, standards of proof necessary to implement regulatory policy differ from those required to resolve legal disputes in the courtroom.[124]

Given the vast differences in proof required in the laboratory and in the courtroom, it is no surprise that the cultural differences between science and the law would be glaring in cases involving toxic torts, where science is most needed. Congress and the courts have attempted to provide guidance in smoothing-out these wrinkles, but not without drawing criticism.

D. Science in the Courtroom – The Critics Speak

Until 1993, the U.S. Supreme Court had not spoken on how the rules of court should specifically apply to science in the courtroom. Instead, the general rule came from a 1923 D.C. Court of Appeals case, Frye v. United States.[125] InFrye, the then Court of Appeals for the District of Columbia stated that the origin of a deduction must be “sufficiently established to have gained the general acceptance in the particular field in which it belongs.”[126] This “general acceptance” test was the dominant standard in this country for over seventy years.[127] When the Federal Rules of Evidence were enacted, critics found them too liberal in the face of the traditional Frye rule.[128] Those espousing the liberal approach maintained that the Federal Rules were designed to expand the admissibility of scientific expert testimony.[129]

For critics of the use of scientific evidence in the courtroom, there is no connection at all between legitimate science and scientific evidence – because it is merely expert opinion itself that constitutes evidence.[130] In fact, anyone claiming to be a scientist need not prove so, for any “self-styled scientist” is welcomed with “open arms” into the courtroom.[131]

A more gentle view of this behavior is that opportunistic lawyers, representing clients with questionably valid illnesses, seize upon tentative scientific results to further the litigious cause.[132] Such attorneys are not only opportunistic, they are driven by the hopes of winning the tort lottery.[133] Supported by the media, politics, fear, or simple outrage, plaintiff’s lawyers take advantage of a legal system that is relatively inept in the face of legitimate science.[134]

Critics believe that not only is the system incapable of handling such matters, but “ordinary citizens are not equipped to sort out the complex scientific issues” associated with toxic tort litigation.[135] Some jurors would go so far as to say that the science offered in the courtroom did not matter to them, only their feelings on the issue.[136] So much for the jury system.[137]

Specific examples of such legal crimes against the honor of science abound. Fed by anecdotes, “irrational theories,” and mass hysteria, the American tort system permitted thousands of litigants to prevail in the courtroom over the safety of silicone-gel-filled breast implants, despite legitimate science to the contrary.[138] While seen by the psychiatric community as being scientifically invalid, psychiatrists in the courtroom are allowed to testify as to the likely future violent behavior of a defendant.[139] Other examples include litigation over spermicides that might cause birth defects, brain disease resulting from exposure to the whooping cough vaccine, and IUDs that did not contain the nylon multifilament tail that got Robins= Dalkon Shield into so much trouble.[140]

To best understand how the definition of “expert” has changed since Daubert and Joiner, one must determine if judges have successfully addressed these criticisms while performing their “gatekeeper”[141] functions. Have the proponents of junk science been continually successful or have they met with resistance in the courtroom? How have federal judges treated experts who fail to support their theories with accepted methodologies? A close analysis of some cases that have applied both the Daubert standard of admission and the Joiner standard of review shows that courts have been very successful in weeding out “bad” experts.[142]


A. Daubert on “Scientific Knowledge” – A Matter of Reliability

In Daubert v. Merrell Dow Pharmaceuticals, Inc.,[143] the Supreme Court attempted to elucidate how the scientific view of “science” should fit into its use in the legal system. Federal Rule of Evidence 702 states that “scientific knowledge” may be presented in the form of expert opinion if “it will assist the trier of fact” in understanding scientific issues. The Court considered the term “scientific” to imply a “grounding in the methods and procedures of science.”[144] It then noted that the word “knowledge” connoted “more than subjective belief or unsupported speculation,” but “any body of known facts or . . . any body of ideas inferred from such facts or accepted as truths on good grounds.”[145]

In interpreting the new Federal Rules of Evidence in the context of the Frye “general acceptance” test,[146] the Court sought to endorse a more objective standard for evaluating scientific expert testimony. In doing so, the Court seemed willing to agree with the conventional scientists’ understanding of what “science” entails.[147] Particularly, the Court agreed with the notion that scientific explanations should be capable of empirical test.[148] The Court also agreed with Karl Popper’s notion of falsifiability.[149] Thus, the first of the four Daubert Principles is whether or not the theory or technique of scientific knowledge[150] has been or is capable of being tested.

Daubert also requires that scientific knowledge has been exposed to peer review and publication.[151] While the lack of publication did not preclude admissibility, publication did not guarantee admissibility.[152] The Court even recognized that valid scientific theories might not be published, perhaps because they are too new or of too limited interest to be published, but still be considered valid science for the purposes of scientific expert testimony.[153]Being submitted to the scrutiny of the scientific community promotes sound science, because it increases the likelihood of detecting methodological flaws.[154] The Court concluded its discussion of peer review by stating that publication, while relevant, would not be dispositive in assessing the scientific validity of a technique or methodology.[155]

The Daubert Court also felt a third necessary component of a methodology’s validity was the ability of the court to consider a known or potential rate error.[156] Statistical significance must rise above a level of mere “suggestiveness.”[157] One court has stated that competent testimony must provide evidence that “a reasonable fact-finder could view as showing a greater than 50% chance of a causal connection” between a defendant’s product and the plaintiff’s illness.[158]

The Daubert decision envisions science as “an empirical enterprise and emphasizes the need for validation through testing.”[159] Mathematical accuracy is perhaps the one immutable characteristic of science that is relatively stable from one member of a scientific community to another in a particular community.[160] The Court also indicated that reviewing judges should consider the “existence and maintenance of standards controlling the technique’s operation.”[161] In the absence of a formal study, however, some situations may allow for the use of anecdotal observations to provide sufficient validation.[162]

Finally, the Court maintained that “general acceptance,” while no longer the sole reviewing criterion, “can yet have bearing on the inquiry.”[163] In seeking to illustrate what might constitute “general acceptance,” the Court extensively quoted a case from the Third Circuit, United States v. Downing.[164] The Downing case involved admission of testimony from an expert in the field of human perception and memory on behalf of a defendant in order to refute the reliability of eyewitness identification. It was also a Rule 702 inquiry for the court.[165]

The Daubert Court particularly agreed with how the Third Circuit discussed a “reliability assessment” in deciding whether to admit novel scientific evidence.[166] The Downing court proposed a more flexible approach to assessing reliability, specifically contradicting the Frye standard.[167] The court in Downing envisioned a reliability assessment that “[did] not require, although it [could] permit, explicit identification of a relevant scientific community and an express determination of a particular degree of acceptance within that community.”[168] If a particular technique has been able to attract only minimal support within a community, then it may not be deemed reliable.[169] But if a novel form of scientific expertise has no established “track record” in litigation, a reviewing court may look to other factors that bear on the admissibility of the proffered evidence.[170]

In the end of its discussion on what constitutes scientific knowledge, the Supreme Court said that a Rule 702 inquiry should be a flexible one.[171] The Court stated that scientific validity would be determined by the principles underlying the submission, focusing “solely on principles and methodology, not on the conclusions that they generate.”[172] The notion that methodology determines the validity of a proposed scientific principle is very much in harmony with how the scientific community perceives “valid” science. The theory must be valid, it must be supported by sound methodology, the results must statistically make sense, and the conclusions drawn must comply with the results.[173]

These pointers only suggest how a court might evaluate the reliability of the proffered scientific testimony. How should a reviewing judge apply these notions of science to decisions over the admissibility of scientific evidence? If the allegation is that methodology is skewed, should the inquiry be a Rule 403 problem, a Rule 702 analysis underDaubert, a Rule 703 problem, or a question of sufficiency for the jury?[174]

D. Daubert and Joiner B Relevance and the Use of Experts

In Daubert, the Supreme Court did more than lay the foundation for determining what “scientific knowledge” would be reliable. It also reminded federal judges of their responsibility to consider how other federal rules interacted with scientific expert testimony. Finally, in Joiner, the Court strengthened the “gatekeeper” role of federal district court judges by holding that their decisions would be overturned only through a showing of “abuse of discretion.”

In Daubert v. Merrell Dow Pharmaceuticals, Inc.,[175] the Supreme Court was asked to rule on the admissibility of evidence regarding a link between birth defects and the anti-nausea drug Bendectin. Although questions regarding the connection between Bendectin and birth defects have been around for thirty years,[176] the Daubert case was less about causation than it was about basic questions on the adaptability of the law. The Frye “general acceptance” test[177] was seemingly at odds with the “liberal thrust”[178] of the new Federal Rules of Evidence, particularly Rule 702.[179] In outlining the screening role of the district court judge in light of the new rules,[180] the Court stressed that that “under the Rules the trial judge must ensure that any and all scientific testimony or evidence admitted is not only relevant, but reliable.”[181]

After determining the reliability of the proffered scientific knowledge,[182] a district court must examine its relevance. The relevance of the proffered testimony, referred to as the Daubert “fit” test,[183] is a second essential inquiry a district judge must make under Rule 702.[184] Rule 702 requires that the proffered evidence or testimony “assist the trier of fact to understand the evidence or to determine a fact in issue.” This is primarily a question of relevance, of “fit.”[185] If the expert testimony does not pertain to any issue in the case, it is not relevant.[186] The Rule 702 “helpfulness” standard requires a legitimate relevance to the core issue as a precondition to admissibility.[187] On remand, the Ninth Circuit rejected the plaintiff’s expert testimony because it failed to prove a specific causal connection between the defendant’s product and the plaintiff’s birth defects.[188] Critics of the relevancy inquiry believe that it inhibits the toxic tort plaintiff’s ability for recovery, placing too much control in the hands of judges who fail to appreciate the scientific evidence.[189]

In addition to its analysis of the gatekeeping role[190] under Rule 702, the Daubert Court reminded federal judges to bear in mind other rules affecting admission of expert testimony.[191] First among these rules mentioned was Rule 703.[192] The Court clarified that the second sentence of the rule permitted otherwise inadmissible hearsay to be admitted if the facts or data were “reasonably relied upon” by other experts.[193] Under Rule 703, a qualified expert may apply his relevant and reliably grounded knowledge and expertise to facts and data in the particular case in order to form and express a pertinent opinion or inference.[194] The facts or data may be derived from (1) the first hand observation of facts, data, or opinions perceived by the witness before trial; (2) the facts, data or opinions presented at trial; or (3) facts, data or opinions presented to the expert outside of court other than by his own direct perception.[195] If they are of a type reasonably relied upon by experts in the field, such facts, data or opinions presented to the expert out of court need not be admitted or even admissible in evidence.[196]

Rule 703 is designed to bring the judicial practice into line with the practice of experts themselves when not in court.[197] It is believed that this language in Daubert seems to acknowledge that Rule 703 provides an independent authority for excluding expert testimony.[198] Several courts have acted on this premise and used Rule 703 to exclude testimony.[199] This often results in a “back-door resurrection of the Frye ‘general acceptance’ test.”[200]

The Daubert Court also specifically stated that district court judges “must determine at the outset” under Rule 104(a) whether the expert is seeking to testify to scientific knowledge that will assist the trier of fact in understanding the underlying scientific issues.[201] Rule 104(a) provides, in part: “Preliminary questions concerning the qualification of a person to be a witness, the existence of privilege, or the admissibility of evidence shall be determined by the court…” The Court added that admissibility should be established by a preponderance of evidence standard.[202] This preliminary assessment of admissibility should be conducted in limine.[203]

Finally, the Daubert Court mentioned that Rule 403 would also permit the exclusion of otherwise relevant and reliable evidence “if its probative value is substantially outweighed by the danger of unfair prejudice, confusion of the issues, or misleading the jury.”[204] Situations where a court would apply Rule 403 in a Daubert inquiry include: Presentation of evidence couched in prejudicial terms, evidence that carries with it the “aura of scientific infallibility,” and situations where in-court presentation of evidence would be so “vivid and compelling” as to distract jurors from its actual probative value.[205] In Joiner, the Supreme Court stressed that “when law and science intersect, [the duties of weighing prejudice and probative value] often must be exercised with special care.”[206]

But these were all matters for the trial court judge to consider, leaving the question open as to the standard of review. In 1997, the Supreme Court answered that open question with its decision in General Electric Co. v. Joiner.[207] In that case, a district court judge excluded testimony that PCBs manufactured by defendants caused the plaintiff’s cancer. The plaintiff had been a smoker for eight years, his parents were smokers, and there was a history of lung disease in his family, indicating that he was “perhaps already at a heightened risk of developing lung cancer eventually.”[208] The defendant’s experts had criticized the testimony of plaintiff’s experts in that it relied solely on animal studies without any support by epidemiological studies.[209]

Shoring the traditional “abuse of discretion” standard, the Court disavowed the Eleventh Circuit’s application of a “particularly stringent” standard of review.[210] The Court rejected the notion that standards of review should change if there is expert testimony involved.[211] It also repelled an argument that a stricter standard of review should be applied if the result of summary judgment was “outcome determinative.”[212] The Joiner Court also stressed that the expert’s analysis needs to be logical in order to survive scrutiny.[213]


Scientific expert testimony is crucial to a plaintiff’s success in a products liability or toxic tort case. Toxic tort cases, which are also sometimes primarily products liability cases, are those that deal with a personal injury or harm resulting from repeated exposure to toxic substances, which may be chemicals, radiation, or biological agents.[214] Plaintiffs typically experience long-term exposures to chemicals or other substances that may eventually cause illness. The injury is often a terminal disease, such as cancer, or syndrome that is cause by an underlying genetic mutation that manifests after the long latency period.[215] Unfortunately, the long latency periods and low dosages involved make establishing a prima facie case extremely difficult.[216]

As a result of the complex scientific issues involved, the plaintiff in the toxic tort case relies solely upon the strength of her witness. The performance and strength of the expert will determine the outcome of a case just as much as the science. Many of the plaintiffs who have failed to have evidence introduced in the wake of Daubert and Joiner have done so because of bad experts. The outcome of these cases also illustrates how Daubert and Joiner have succeeded in addressing criticism from the scientific community and, hopefully, changed the perception of “experts” relied upon in the courtroom.

A. Examples that Illustrate Daubert’s Success in Weeding-out Bad Experts

While opponents of “junk science” in the courtroom may truly have a grudge against the underlying science itself,[217] they often are more concerned with the “charlatans” promoting the science, using the courtroom to achieve legitimacy. Daubert has been very successful in addressing this criticism by excluding questionable methodologies, practices, and performance of experts in the courtroom,[218] as the following examples will illustrate.

1. Failing to Meet the Reliability Requirement of Daubert

While experts are necessary to prove causation in toxic tort cases, a plaintiff should chose its experts carefully. Rule 702 mandates a preliminary inquiry into the qualifications of the expert.[219] Surprisingly enough, choosing an expert who lacks the knowledge needed to offer an opinion is a common problem.[220] It may also be detrimental to choose an expert who lacks a certain level of experience.[221] It is certainly damaging to a plaintiff’s case to select an expert who is not qualified to testify on the science that pertains to that plaintiff’s claim.[222] Finally, judges will exclude an expert who himself discounts the theory behind the claim.[223]

Even with a good expert, testimony has been excluded when the expert failed to properly use published research, which is relevant under the Daubert factor governing peer review and publication. Some courts have found it significant that the plaintiff’s experts could point to no research that supported their position.[224] Courts have also excluded expert testimony when the literature cited specifically disavowed the causal connection a plaintiff was attempting to prove.[225] Judges have been skeptical when the expert makes vague references to the scientific literature, without providing sources.[226] Despite fears about sophisticated scientists fooling unsophisticated courts, judges have shown that they can identify when an expert is improperly applying published research.

Underlying judicial review of expert testimony is the necessity of ensuring that the methodologies employed were valid. As the Daubert decision mandated, the focus should be on the methodologies, not the conclusions. Courts have proven very successful in using this focus to eliminate potentially false methodologies. Experts who claim to use methodologies unique to themselves have not been permitted to confuse the courtroom with their haphazard processes.[227] Courts can also recognize when an expert simply did not know how to apply accepted methodology.[228] It has also been unacceptable for an expert to apply the incorrect methodology, even if it was valid.[229] Courts have been successful in excluding testimony based on general impressions rather than methodology.[230] Courts have also required that research on which the expert relies must have been conducted prior to and independent of litigation.[231] Finally, courts have excluded testimony if the expert simply provides inadequate exposure proof.[232]

To say that all of these experts applied questionable, dubious, and incorrect methodologies is an understatement. How these district courts have handled the experts illustrates how capable they are of fulfilling their gatekeeping functions and ensuring that the science offered is “reliable.” In addition, members of the scientific community can take comfort in the Joiner standard and its ability to ensure that these decisions will remain undisturbed at the appellate level.

2. Failing to Meet the Relevance Standard of Daubert

In order to fulfill their gatekeeping responsibilities, however, courts must also ensure that the proffered scientific testimony is relevant to the case. Critics have claimed that the unsophisticated can be easily misled, that it may be easy for a sophisticated expert to use the wrong scientific methods. As courts correctly applying the Daubertrelevance test have shown, these fears are not well founded. A proffered scientific study must be applicable to the plaintiff’s illness; analogies will not suffice.[233] Courts will also not permit experts to claim that if a chemical is known to cause one illness, it must be able to cause another.[234]

3. Generally Poor Trial Strategy or Expert Performance

Assuming that a plaintiff has a good expert and science on his side, judges may still find other reasons for excluding testimony. First of all, one can simply have a “bad” plaintiff. For example, courts may not be willing to allow weak causation testimony in the courtroom if it is clear that the plaintiff’s lifestyle may have contributed more to his illness than the defendant’s product.[235] Courts have not been sympathetic to plaintiffs who fails to address Daubert, either in the Supreme Court’s decision or the Ninth Circuit’s remand decision.[236] In addition, judges have also excluded experts who clearly were uncertain of their own opinions under examination.[237] Judges have also excluded testimony when the expert appeared to be changing causation testimony from previous statements made in affidavits.[238]Experts who cannot even recall the gist of their research have also been met with justifiable skepticism.[239] Judges have also considered an expert’s testimony inadequate if it failed to address the majority of the plaintiff’s claims.[240]

Holding the plaintiff and her experts accountable to methodology and relevance has not an absolute bar to success. The following example illustrates how judges can admit novel scientific evidence through a thorough Daubertanalysis and good expert performance.

D. How Plaintiffs Have Been Successful in Introducing Novel, but “Valid,” Science

There are few toxic tort or products liability cases involving a DauberJoiner analysis where the plaintiff has been successful in introducing expert testimony. This can be viewed either a testament of the ability of courts to successfully “weed out” “junk science” or as proof of their propensity for being favorable to defendants. After analyzing the previous cases, however, it is clear that proper application of Daubert and Joiner to toxic tort cases usually does not screen novel scientific theory, only bad experts.

One of the finer examples of a successful plaintiff under a DaubertJoiner application in a toxic tort case is Zuchowicz v. United States.[241] Patricia Zuchowicz initiated a suit[242] under the Federal Tort Claims Act,[243] claiming to have developed primary pulmonary hypertension (PPH) as a result of the defendant’s negligence in prescribing an overdose of Danocrine. Both parties in the case agreed as to the injury and the defendant’s complicity in the overdose, but sharply differed on causation.[244] The plaintiff faced two significant barriers: PPH was an extremely rare disease and few human beings had ever been subjected to the dosage that caused the plaintiff’s illness and eventual death.[245]As a result, the plaintiff’s experts were unable to provide any epidemiological or anecdotal evidence linking PPH to Danocrine overdoses.[246]

To overcome these shortcomings, Dr. Matthay established a temporal relationship between the overdose and the start of PPH and ruled out other drug-related causes through a differential diagnosis.[247] He compared similarities between the course of Mrs. Zuchowicz’s illness and that of accepted cases of drug-induced PPH.[248] Dr. Tackett testified that the overdose of Danocrine caused the PPH by reducing estrogen levels, and producing elevated levels of insulin, free testosterone, and progesterone.[249] In concluding that these factors likely caused a dysfunction of the endothelium leading to PPH, Dr. Tackett relied on a variety of published and unpublished studies that indicated these factors could cause endothelial dysfunction and an imbalance of vasoconstrictor effects.[250] Since Danocrine had never before been linked to PPH, the defendant contended, the district court should never have admitted the expert testimony.[251]

The Second Circuit disagreed. In reviewing the district court’s decision to admit testimony for an “abuse of discretion,”[252] the Second Circuit relied upon the four Daubert factors and a previous Second Circuit decision[253]to evaluate the scientific methodology. The district court concluded each expert “clearly possesse[d] expert scientific knowledge.”[254] As to the methodology employed by the experts, the Second Circuit stressed the flexible nature of the Daubert inquiry.[255] The Second Circuit concluded that the district court properly fulfilled its gatekeeping role, admitting the testimony of well-credentialed experts relying on scientific methodology.[256] It also agreed with the district court’s conclusion that the experts “based their opinions on methods reasonably relied upon by experts in their particular fields.”[257]

While the system remains far from perfect, as does the scientific process itself, examination of post-Daubert and post-Joiner cases shows that many of the scientific community’s criticisms have been addressed. Proper application of theDaubert standards, coupled with the “abuse of discretion” standard of review reaffirmed by Joiner, may lead to a reduction in the admission of experts, but it leads to an increase in quality and reliability. While few lawyers would say it outright, the legal system seeks justice, but it also seeks credibility. Establishing credibility of the process is a fundamental goal of the Federal Rules of Evidence. Increased quality of experts in the courtroom contributes to both. The end result does not need to be fewer experts, but better ones. It should also lead plaintiff’s attorneys to pause and think before accepting a case. Merely because someone is ill does not necessarily mean that they have a cause of action. Some cases cry for justice but, in the end, there may be nothing we can do.[258]

The Zuchowicz case illustrates how judges can admit novel scientific expert testimony in a post-Daubert, post-Joinercourt. Well-credentialed experts, internally consistent theories, and valid methods relied upon by other members of an expertise provide judges sufficient justification for admitting novel scientific evidence. But what if the science is so novel that it does not fit into these conventional models? Should courtrooms be forever closed to such claims? Do courts need to adjust their paradigms to meet these new theories? These questions are addressed in the following discussion on MCS.


Saying you are a clinical ecologist to members of some of the “legitimate” scientific fields is similar to proudly identifying yourself as an “ambulance chaser” in a room full of state supreme court justices.[259] Sneers, loathing, and upturned noses are sure to follow. That is because clinical ecologists promote the “junk science” known as Multiple Chemical Sensitivities, or MCS.[260] According to opponents, clinical ecologists not only promote their pet illness, they invented the hysteria.[261] Some scientists even feel threatened by the field of clinical ecology.[262]

Opponents of MCS most likely consider it what scientists refer to as a “Cheshire fact,” that is, something “solemnly recorded, earnestly explained, vehemently defended, and then never seen again.”[263] Most certainly, MCS and its underlying theories are of the sort that would be considered “absurd and irrational pseudoscientific assertions.”[264]

MCS patients also share the scorn of legitimate science. Persons claiming affliction via MCS are referred to as neurotic,[265] or “very seriously nuts.”[266] At the very least, they may be considered social deviants.[267] This perception of the environmentally afflicted leads more to marginalization than to treatment.[268]

Yet thousands of people in the United States and Canada claim to be afflicted with this illness or syndrome. Clinics have been established to treat the MCS infirmed.[269] Professional organizations have been established that publish journals and establish treatments for MCS.[270] This section discusses the scientific quandary that is MCS and how courts have addressed the controversy through Daubert review.

A. The Nature of MCS – Theories, Symptoms, and Treatments

One author has suggested that the perceived illness of MCS originated with the publication of two books in 1962: Rachel Carson’s Silent Spring and Dr. Theron G. Randolph’s Human Ecology and Susceptibility to the Chemical Environment.[271] Multiple chemical sensitivity is known by many names, most of them associated with the perceived cause of the particular illness. Some of the more common names include “sick building syndrome,” “environmental illness,” “total allergy syndrome,” and “twentieth-century disease.”[272]

The fundamental theory of MCS is that various types of environmental “insults” may overload a person’s immune system to the point that the exposed person becomes hypersensitive to chemicals, odors, or other naturally occurring substances.[273] MCS has also been compared with classic pavlovian conditioning and with psychophysiological models of conditioning theory.[274] Underlying these theories is a belief that each person suffering from the illness will develop a syndrome unique to their situation.[275]

The symptoms associated with MCS are numerous. At one Toronto clinic, patients complained of sensitivity to odors, neurological symptoms, allergies to food or medication and breathing problems.[276] Specific symptoms cited number over one hundred, including swelling or pain in joints, nasal or sinus difficulties, hypersensitivity to sounds and smells, abnormalities in breathing and pulse rate, fatigue, skin irritation, nausea, and various gastrointestinal disorders.[277] These myriad symptoms tend to originate from several systems, including the nervous, muscular, respiratory, gastrointestinal, and cardiovascular systems.[278] But according to the American Academy of Allergy and Immunology, there is no evidence that these symptoms are caused by anything at all.[279]

Despite these assertions, several triggers for the illness have been suggested. Organic solvents, bacteria or fungus, pesticides, perfumes, petrochemicals, and many other unrelated chemicals are believed to trigger the onset of the illness, usually transmitted via the olfactory systems.[280] At least one study has concluded what does not cause MCS.[281] Adding to the confusion, no one has been able to determine why some chemicals trigger MCS and some do not.[282]

Given that there are multiple symptoms and theories of causation associated with the illness, it should come to no surprise, then, that medical practitioners apply a variety of treatments to MCS patients. There are two general areas of treatment that MCS patients undergo: those that are self-enforced and those practiced by the physicians treating MCS patients. Most common among the self-imposed treatments are avoidance regimens, where patients attempt to avoid the chemicals or substances they believe contribute to their condition.[283] The most well-known of the clinical treatments for MCS is a process known as the “provocation-neutralization” method.[284]

There is also no consistency in the types of people who are afflicted with MCS. Studies have shown that those affected by MCS include industrial workers, those who work in airtight buildings, people exposed to chemicals in consumer products, chemical accident victims, people who live in areas with higher concentrations of water and air pollution, and people living near toxic waste sites.[285] However, studies on MCS consistently show that the patients tend to be predominantly females in their forties.[286]

Every “recognized” medical organization denies the existence of MCS as a physiological illness. Reports on MCS have been criticized on technical grounds because the studies reflect individual reports of patients rather than controlled clinical or epidemiological studies.[287] Courts consistently agree to concede to these professional organizations.[288]The following discussion accounts how federal courts have applied the Daubert test to admissibility of MCS causation evidence.

B. “Which One of These Does Not Belong?” Or, How MCS Doesn’t Fit in With the Other Illnesses

One of the “problems” with MCS is that it does not conform to any widely accepted concepts of illness. It is not accepted in the “normal science” community because it does not fit into any “relatively inflexible box” of existing immunological, epidemiological, or toxicological paradigms.[289] It is the very nature of science that some theories stubbornly refuse to be assimilated into existing paradigms. While this pattern gives rise to new theories, which, in turn, advance science,[290] something about MCS brings the “true” scientist’s blood to a boil and causes the defending attorney to return to a primordial, bestial state.

Another problem is that the etiology[291] for MCS is not known.[292] Several immunologic, neurotoxic, and psychiatric causes have been proposed.[293] Some common triggers include personal stress, surgery, and reaction to a new building.[294] But, for the most part, the onset of MCS is not accompanied by a single isolating event; it is not a “signature illness.”[295] Therefore, a simple model based on isolating singular cause-and-effect relationships is useless in trying to explain the occurrence of an illness that is caused by several factors.[296]

MCS sufferers also display a vast array of symptoms,[297] far too many for those in traditional scientific or medical practices to accept.[298] But MCS is not the only recent illness to suffer this defect. The thousands of women who have experienced illness from exposure to silicone gel implants have also displayed a vast array of symptoms.[299]Veterans from the Gulf War have experienced as many as six distinct and documented syndromes, each with unique symptoms, all under the commonly known heading of “Gulf War Syndrome.”[300] The types of symptoms associated with MCS also places the illness outside of conventional paradigms.[301]

Even the self-defined name “clinical ecology” does not make any sense. Clinical ecology covers a vast array of clinical and scientific disciplines.[302] The label of “clinical” is relatively accurate, as it implies the direct treatment and observation of patients, as opposed to experimental or laboratory science.[303] However, associating the word “ecology” suggests the relationship between an organism and its environment, or a biological study of those relationships.[304] This environment in which the organism lives is its “ecosystem.” This common understanding of the term “ecology” does not fit well when the only organism being studied is humans, and the environment is limited to an industrial one.[305] Perhaps “industrial ecologist” would be more accurate.

C. Success of the MCS Plaintiff – An Unhappy Day in Court

No single district court has admitted causation testimony regarding MCS and only one circuit court has reviewed the evidence after Joiner.[306] The mere allegation that a plaintiff is claiming to suffer from MCS is enough for a district court to dismiss the case, regardless of what an expert might have to say.[307] Courts reviewing MCS causation testimony have excluded it for essentially two reasons: the etiology of MCS is unknown, and the existence of the illness and the practice of clinical ecology are not “generally accepted” in the medical or scientific community. Only one court has conducted a thorough analysis of all four Daubert reliability factors and the relevancy test.[308]

The lack of acceptance of MCS and clinical ecologists by the scientific and medical community seems to be the foremost justification for denying the admissibility causation testimony. To support a belief that MCS and its progenitors, the clinical ecologists, are not generally accepted in the scientific community, some cases[309] cite to Kenneth R. Foster and Peter W. Huber’s Judging Science: Scientific Knowledge in the Federal Courts, which states:

Chemical ecologists have failed to provide criteria that allow a doctor to decide when somebody does not suffer from MCS which is one of the main reasons why MCS is regarded skeptically be mainstream medicine.[310]

The Federal Judicial Center has voiced similar concerns, also well taken by the courts, regarding the reliability of clinical ecologists and their methods:

Clinical ecologists have not been recognized by traditional professional organizations within the medical community . . . The leading professional societies in the fields of allergy and immunology have rejected clinical ecology “as an unproven methodology lacking any scientific basis in either fact or theory.”[311]

Oddly enough, the cases that cite to this passage from the Reference Manual exclude the textual references to studies that support the claims of clinical ecologists.[312] Statements by the American Medical Association and various other professional organizations about the perceived illegitimacy of MCS and clinical ecology have also been afforded great weight by courts reviewing MCS causation evidence under Daubert.[313] In some cases, this lack of general acceptance alone was sufficient justification for not allowing the evidence into the courtroom.[314] One court even declined to conduct its own independent review of clinical ecology and the science of MCS, citing lack of general acceptance as reason enough to exclude causation testimony.[315]

Beginning with the Bradley v. Brown,[316] the second most expressed reason for denying admissibility of MCS causation testimony is the unknown etiology of the disease. Without specifically applying the four Daubert standards and conducting a general discussion on the “speculative” nature of MCS, the Bradley court stated that “the ‘science’ of MCS’s etiology has not progressed from the plausible, that is, the hypothetical, to knowledge capable of assisting a fact-finder, jury or judge.”[317] To support this conclusion, the Bradley court discussed the various suspected theories behind the etiology,[318] sources that indicate a need for further study on the etiology,[319] other sources that indicate the controversial and speculative stage of the science of MCS at this time,[320] and even the experts’ own testimony.[321]

In only one case, Zwillinger v. Garfield Slope Housing Corp,[322] has a court taken the extra steps to look beyond general acceptance and the uncertain etiology of MCS. In Zwillinger, the district court conducted a full analysis of theDaubert admissibility standards. For the first prong, whether the expert’s theory has been empirically tested, the court focused on a studies relating to the toxic effects on mice of chemical outgassing, particularly the substance 4-PC, from new synthetic carpets.[323] The court concluded that the studies cited by the plaintiff’s expert not only failed to support the outgassing theory, but in fact refuted it.[324] The court also examined a study currently in progress by the plaintiff’s expert, concluding that it was not reliable because it did not use a control group and failed to utilize an animal study to test exposure levels and toxicity.[325]

Due to its thorough analysis of the underlying methodology, the court spent considerably less time on the remainingDaubert factors. Under the peer review analysis, the court acknowledged that various studies had been published regarding the effects of carpet emissions on mice, but that the expert’s own study had not yet been subjected to publication or peer review.[326] Regarding the third prong of the Daubert analysis, the court concluded that not only was there not a known rate of error for the study, the likelihood was very high that the error rate would be substantial.[327] In applying the fourth Daubert reliability prong, the court concluded that the expert’s theories were not generally accepted in the relevant scientific community.[328] Finally, the court also concluded that the expert’s testimony did not “fit” the facts of the case because he did not apply the proper methodologies required for general and specific causation,[329] thus failing the relevancy requirement.

It is quite evident that, while federal courts have mostly used the Daubert and Joiner standards to keep bad experts out of the courtroom, the result has been quite different with MCS. With MCS, it is the science that courts find objectionable. This result has clearly come from an over-emphasis on etiology and general acceptance. In this regard, federal courts have failed abysmally in their application of Daubert. The following section illustrates how judges could allow some, but not all, of MCS expert testimony to be admitted while still remaining true to Daubert.


While MCS does not fit into any accepted paradigms of illness, that should not be a bar to admitting causation testimony.[330] This section discusses matters of science and Daubert that might help a plaintiff get novel scientific evidence into the courtroom.[331] While the focus of this discussion remains on MCS, these standards could easily apply to other novel scientific theories. This is not to say that it is the lawyer’s job to prove or disprove a phenomenon.[332] Such matters should be left to the scientists.[333] But lawyers are required to find quick, final solutions and help their clients to the best of their abilities, with available law and science.[334]

As the case of MCS illustrates, it is all too easy for federal courts to fall into a de facto application of the Frye general acceptance test in the face of novel scientific theory. Judges should review with greater skepticism a proclaimed lack of general acceptance and determine if the underlying methodologies are “grounded in the scientific method,” regardless of whether or not they are “traditional.” Fulfilling these two elements covers at least three of the four prongs of the Daubert reliability assessment, and cover the relevance assessment.[335] Applying these arguments to the review of MCS evidence by federal courts will help illustrate the best way to have novel scientific theory admitted.

A. General Acceptance within the Relevant Scientific or Medical Community

The Supreme Court in Daubert said that general acceptance, while still relevant, is not an absolute test of the reliability of the proffered testimony.[336] If courts are to bring judicial practice into line with the practice of experts themselves while not in court,[337] then general acceptance and peer review should be given less weight since most objective evaluations of the scientific method do not include either factor as a basis for valid methodology.[338]

Despite this assertion, federal courts have almost consistently treated the lack of general acceptance of MCS as an absolute bar.[339] There are several reasons why MCS and clinical ecologists are not “generally accepted” in the scientific community, and these reasons are also directly tied into the lack of peer review or published studies in “reputable” journals on the subject.

First of all, clinical ecologists and other scientists and practitioners who believe in the existence of MCS employ practices and procedures that are not traditional.[340] They utilize tests with different names like “provocation-neutralization”[341] and “SPECT”[342] that are not traditional testing methods. While based on traditional allergist models, clinical ecologists utilize a method of skin testing that varies slightly from the norm.[343]

Second, the traditional medical and scientific communities have a bias against anything that has the label of clinical ecology, regardless of any scientific validity.[344] This is particularly focused on Dr. William J. Rea, director of the Environmental Health Center in Dallas, Texas.[345]

Part of the confusion in the courts is a lack of understanding of what constitutes the relevant scientific community. No cases, particularly not MCS cases, have discussed which community should be considered “relevant” for Daubertpurposes. Criticism of MCS and clinical ecology comes from toxicologists, epidemiologists, and immunologists. Yet none of these critics are members of the clinical ecology community.

If the focus were to remain on clinical ecologists, excluding other practitioners who treat MCS patients, then the relevant organization would be the American Academy of Environmental Medicine (AAEM), not the AMA. This would be consistent with the Ninth Circuit’s Daubert remand decision.[346] Thus in limiting the scope of the community, a plaintiff greatly increases the chance of successfully arguing that the methodologies are employed by “members of the relevant community.”[347]

Much has been made of the perceived “bias” and “subjectivity” of MCS diagnoses,[348] but courts have failed to recognize the inherent bias that MCS opponents have against the disease and how that affects the extent to which MCS has been “recognized” by the “scientific community.” This bias illustrates the inherent difficulty and potential for abuse associated with giving the “general acceptance” test such weight. It also provides a good foundation for arguing a different understanding of the definition of “relevant scientific community,” particularly in light of theDaubert and Downing understanding of the concept.

B. The Science Behind MCS – Theories Grounded in Known Scientific Fact

One of the fundamental barriers to acceptance of MCS is the seeming ridiculousness of its fundamental premise: that life in industrial society can simply overload the body’s immune system.[349] The concept of MCS is not the grand leap from already “accepted” medical and scientific knowledge that the AMA would have federal courts believe. MCS claimants certainly are not alleging that their illnesses are being caused by alien implants.[350] Such a claim would most certainly be “unscientific.”

A plaintiff trying to stress the scientific nature of expert testimony should remind the court of the purpose behind Rule 703, and that is to ensure that scientific fact, not fiction, finds its way into the courtroom. Many of the fundamental theories and principles behind MCS are already accepted scientific fact, yet courts continue to reject MCS.

First, it is well known that the vast majority of diseases are caused by environmental factors.[351] Four groups of environmental factors may adversely affect health: (1) psychological factors, such as stress in the workplace or in human relationships; (2) accident factors, such as speed, and the influence of alcohol or drugs; (3) biological factors, such as bacteria, viruses, or parasites; and (4) physical factors, such as noise, climate, lighting, radiation, and ergonomics.[352] The effects of exposure can range from subtle physiological conditions to severe illness or death.[353]

Immunologists have also identified several kinds of toxic effects of chemicals on the immune system. Some of the identified toxic effects include immunosuppression, which is a change or suppression in immunological functions following exposure to chemicals; and hypersensitivity to chemicals or therapeutic drugs, which can result either in allergies or in attacks by the immune system against the body’s own cells (autoimmunity).[354] Science has also proven that some people are more sensitive, even to common chemicals, than others.[355] Three lines of indirect evidence provide support for the links between chemical exposure and human disease resulting from immune system suppression.[356] Similar evidence suggests possible links between chemical exposure and autoimmune disorders.[357]

In addition, the lack of known etiology is not the litmus test of unscientific knowledge as MCS opponents and courts suggest. If that were truly the case, then no federal court would allow causation testimony on cancer.[358] A close look at cancer also provides some parallels to the criticism against MCS as an illness. Cancer victims undergo varying treatments,[359] their bodies are affected differently,[360] and they manifest a variety of symptoms.[361] Cancer patients particularly may show psychological symptoms due to prolonged illness.[362] Thus, it is possible for theories behind an illness to be based on scientific fact, even when all of the answers are not known.

C. Methodologies of MCS are Grounded in the Scientific Method

A plaintiff must make a prima facie showing, typically under Rule 104(a), that a methodology is “reliable.”[363] The chosen methodology will be rejected if its application is so flawed that it does not constitute scientific knowledge.[364] In this sense, the Daubert Court asserted that such knowledge must be grounded in the scientific method. As previously stated, scientific disciplines differ greatly on what methodologies should be applied. Yet scientists agree that at the heart of every methodology there must be a sound theory, a hypothesis, and some means of testing that hypothesis.[365] As previously mentioned, it is accepted scientific knowledge that toxic chemicals adversely impact the immune system.

One possible source of confusion for courts is deciding which methodology should be applied in determining causation. A good defense attorney will argue that if it does not fit into readily accepted criteria, it does not belong in the courtroom.[366] Unfortunately, many of the “hard science” methodologies are not readily adaptable to MCS. Those methodologies usually assume a linear relationship between exposure and illness; that is, isolating single independent variables, relating them to dependent variables, controlling for bias, and applying these principles to predict future results.[367] Causation theories for MCS are more nonlinear, not easily fitting into this limited paradigm. Perhaps observational epidemiological studies would be useful in applying to MCS claims since they rely less on statistical, linear relationships, allowing for the expert to draw inferences from observation.[368]

Given that clinical ecologists come from a variety of backgrounds, which is the proper methodology to use in presenting causation evidence? The easy question to answer is what methodology an expert should not utilize, at least at the present, and that is the provocation neutralization method. Independent of what some scientists and organizations think of the method, it has not been accepted by the courts.[369] Clinical ecologists themselves dispute its validity.[370] While there may be some valid scientific merit to the procedure, there exists enough controversy at this time to question its usefulness to the courts.

Many judges will not accept any methodology other than toxicology when it comes to admitting causation evidence for toxic tort cases. This is a practice based on a misconception. Contrary to what some commentators claim,[371]toxicology is not the only useful methodology for proving illness causation. Allergy and immunology methodologies are also helpful in understanding illness causation and have been admitted by courts.[372]

One useful approach for the plaintiff might be to rely on a strictly clinical approach, focusing on application of a differential diagnosis.[373] Differential diagnosis is a “patient-specific process of elimination that medical practitioners use to identify the ‘most likely’ cause of a set of signs and symptoms from a list of probable causes.”[374] The expert presenting this evidence must be a physician who has considered the history of the patient’s symptoms, reviewed outside records, conducted a physical examination and laboratory testing, then evaluated all the potential causes for the condition, and ultimately selecting a diagnosis that best fits the findings.[375] While ruling out potential causes of illness, an expert must be careful to include known possible causes.[376] Several courts have held that differential diagnosis passes Daubert muster.[377] The Second, Third, and Fourth Circuits have also held that a clinical physician may express an opinion that is based on clinical medical methodology generally accepted in that discipline, without hard scientific support, while still being consistent with Daubert.[378] In addition, standards of general acceptance do not apply to differential diagnosis.[379]

Finally, the methodologies employed by clinical ecologists are not as entirely unscientific as courts have been led to believe.[380] Clinical ecologists personally take exhaustive patient histories, not entirely self-reported histories.[381]They take complete physical exams of their patients as well as comprehensive laboratory testing of blood samples.[382] The SPECT and skin testing utilized by clinical ecologists, though unconventional, are examples of methodologies that are testable and repeatable, going beyond mere subjective speculation.[383]

D. Experts and the Balancing of Extremes

One question that has not been an issue for courts evaluating MCS is whether or not a plaintiff has presented a suitable expert because most experts are qualified with few exceptions.[384] How a court will examine the qualifications of the expert will depend on what type of expert the plaintiff seeks to use in her case.[385] There are some general characteristics that each expert should possess, regardless of field. These would include an advanced degree, research or practical experience specifically related to the field, certification to practice in the field by a specialized board, membership in a professional organization related to the field, and other indications of expertise, such as selection for national advisory panels relating to the subject.

Plaintiffs should remind the court that the balancing of extremes in admitting or denying scientific evidence into the courtroom was the primary objective behind the Supreme Court’s decision in Daubert. For those who argued against abandoning the Frye “general acceptance” test, the Court stated that traditional trial techniques of cross-examination, introduction of contrary evidence, and proper jury instructions were more than adequate to filter out invalid scientific testimony.[386] For those who feared the screening role of the judge would stifle scientific ingenuity, the Court was less comforting. While recognizing the differences in the scientific and legal search for the truth, the Court admitted that sometimes a jury would be denied access to “authentic insights and innovations,” but that is just how it goes sometimes in the name of fairness and justice.[387] To continue on the present course and categorically deny MCS plaintiffs admission into the courtroom violates the balance sought by Daubert.


Lawyers should never leave it solely up to scientific experts to educate the court on science. That education should begin with each plaintiff’s lawyer, during consultation.[388] Lawyers should seek out partners who are knowledgeable about scientific processes, or should educate themselves on the issues.[389] Lawyers as well as judges should become more familiar with the scientific issues regarding risk assessment.[390] More importantly, judges who frequently deal with these issues should themselves become more acquainted with scientific issues and processes.[391] The haphazard review of scientific evidence in MCS cases, coupled with the obvious bias of the scientific and medical community against the disease, has shown that perhaps judges should become amateur scientists,[392] at least to the point where they can recognize independently what constitutes a scientific method.

The fact that no federal judge has sanctioned a plaintiff’s attorney for bringing a frivolous claim illustrates that courts are not opposite to admitting MCS causation evidence; they simply believe that the science doesn’t support it at this time. While waiting for the science to “catch up” with the needs of MCS clients,[393] plaintiffs’ attorneys may have to simply get what they can for their clients. Courts have not allowed causation testimony under Daubert, but they have permitted experts to testify regarding the effects of MCS for cases involving Fair Housing Act[394] discrimination cases.[395] While some employers have made accommodations for MCS sufferers,[396] plaintiffs have met with less success in using the ADA[397] to compel employers to provide those accommodations.[398]

While the courtroom should not be a forum to prove “junk science” theories,[399] it should also not cater to the whims of the scientific intelligentsia. A misapplication of Daubert and de facto resurrection of Frye merely permits the scientific community to dictate legal causation in the courtroom. Just because a scientific theory does not bear the AMA stamp of approval does not mean it cannot be “helpful” to the trier of fact.[400] It is the responsibility of lawyers and judges, as ambassadors of the law, to preserve it and their professional reputations. The law is not served by defendants’ attorneys who are openly hostile to toxic tort claimants[401] any more than it is by plaintiffs’ attorneys who bring questionable claims.[402]

The application of Joiner adds one additional quandary for the toxic tort plaintiff. No single circuit court has held that a district court abused its discretion for excluding causation evidence relating to a toxic tort or products liability claim. One court, however, held that a district court abused its discretion for admitting such evidence.[403] With that in mind, the importance of a strong showing during a motion in limine becomes even more apparent. Joiner provides additional incentive to succeed at the district court level, or not succeed at all.

In closing, the quandary over the use of environmental experts in the courtroom is one that will not be resolved any time soon. Scientific and legal differences over standards of proof and the use of science in the courtroom lie at the heart of this controversy. The Daubert and Joiner cases have significantly answered many of the criticisms levied against the courtroom by scientists, reinforcing a vision of the environmental expert as one grounded in the methods of science. As a result, the road ahead for the plaintiff trying to admit novel scientific theories into the courtroom is long and hard. While Daubert stressed a more liberal standard than the traditional “general acceptance” test, courts have consistently applied the Frye rule, albeit under the guise of Daubert, against MCS claimants. If judges will not seek to conduct thorough reviews of the science, it is up to the plaintiff’s lawyer and experts to properly educate the court on matters of science.



* J.D. 1999, University of Minnesota Law School; B.A. 1994, University of Minnesota. The author would like to thank Kari Thoe and Professor Jim Chen for their advice and assistance.

[1] Michael A. Frohman, The Limits of Genetic Engineering, NEWSDAY, July 6, 1993.

[2] See Ann Kellan, A Sheep Cloning How-To, More or Less, (broadcast on February 24, 1997) <>>.

[3] See STEPHEN JAY GOULD, THE MISMEASURE OF MAN 21 (1981) (referring to the objectivity of science as a “myth” that can only become reality “when scientists can shuck the constraints of their culture and view the world as it really is”).

[4] Id. at 22.


[6] Novel science refers to theories or evidence that have not achieved acceptance by mainstream scientific or judicial communities. See 3 J. WEINSTEIN & M. BERGER, WEINSTEIN’S EVIDENCE & 702[03], at 702-43 (1995); United States v. Downing, 753 F.2d 1224, 1231-39 (3d Cir. 1985).

[7] See generally GOULD, supra note 3.


[9] See generally R.A. Deyo et al., The Messenger Under Attack, 336 NEW ENGLAND J. MED. 1176 (1997) (describing attacks by industry on scientists who publish data relevant to “hot button” policy issues or massive liability claims);Intimidation of Researchers by Special-Interest Groups, 337 NEW ENGLAND J. MED. 1316 (1997) (criticizing peer journals that publish studies sponsored by industries that are trying to defend against large liability claims); W. Roush, Publishing sensitive data: who calls the shots? Secrecy dispute pits Brown researcher against company, 276 SCIENCE 523 (1997). Cf. Lawrence K. Altman, The Doctor’s World: Hidden Discord Over Right Therapy, N.Y. TIMES, Dec. 24, 1991, at B6 (making strong connections between scientific journals, academia, and the pharmaceutical industry).

[10] See H. Josef Hebert, Foes Seek to Muzzle Global Warming Talk, THE RECORD (Northern New Jersey), July 7, 1998, at A8 (discussing attempts by the House of Representatives to include in an EPA appropriations bill a prohibition of any education or discussion on global warming by the Clinton Administration). Global warming is a condition where the Earth’s atmosphere is heated at an unnatural rate, caused mostly by the release of various gases into the atmosphere, chief among which is carbon dioxide. See BARRY COMMONER, MAKING PEACE WITH THE PLANET 10 (1990). Many petrochemical manufacturing byproducts and gaseous emissions from internal combustion engines contribute to this process. See id. While it is generally accepted in the scientific community that global warming exists, those in the coal and petroleum industries and their supporters in Congress insist that it is a hoax. See, e.g., Hebert, supra this note, at A8 (recording Robert E. Murray, President of the American Coal Co., as saying that global warming is a hoax); 141 CONG. REC. E2053 (daily ed. Oct. 26, 1995) (remarks of Rep. Delay) (“despite the public scare campaign by environmental extremists, the reports of destructive global warming have been greatly exaggerated”); id. at E2270 (daily ed. Nov. 30, 1995) (remarks of Rep. Istook) (“the theory of global warming is not supported by the facts. The scare mongers would have us shut down our domestic energy production based upon falsehoods. The scare mongers are receiving grants from taxpayers to attack taxpayers’ livelihoods”).


[12] See Frank v. State of New York, 972 F.Supp. 130, 132 n.2 (N.D.N.Y. 1997).

[13] See Studies of the Prevalence of Chemical Sensitivity and MCS, (updated July 4, 1998) <> (citing several studies conducted by clinicians and state agencies regarding the prevalence of reported and diagnosed symptoms of MCS in selected states); Charlotte Gray, Waiting list already 7 months long at Toronto’s new Environmental Health Clinic, 156 CAN. MED. ASS’N J. 879, 880 (1997) (discussing study of 4000 patients in the Toronto area alone who had health problems related to chemicals or the environment).

[14] See Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 1001 (C.D. Cal. 1995) (mentioning such “distinguished bodies” as the American College of Occupational and Environmental Medicine, the American Medical Association, the American College of Physicians, the American Academy of Allergy and Immunology, and the California Medical Association), Simon et al., supra note 265, at 98 (“A recent report of the American Medical Association’s Council on Scientific Affairs concluded that ‘multiple chemical sensitivity should not be considered a recognizable clinical syndrome'”). This last point once again illustrates how MCS fails to fit into “recognizable” paradigms. That does not mean, however, that it should be considered invalid.

[15] If one were to rely on the case law and the statements by Kenneth Foster and Peter Huber, one would think that only clinical ecologists treat MCS patients or are conducting MCS research. This is patently false. The following is a list of some practitioners who conduct MCS research or treat MCS patients who are not clinical ecologists.

1. Claudia Miller, allergist-immunologist at the University of Texas Health Science Center in San Antonio, Texas. Formerly an industrial hygienist for the University of California Medical Center in San Francisco, the Occupational Safety and Health Administration, and finally the United Steelworkers Union. She currently does research in environmental and occupational health in the University of Texas Health Science Center=s Department of Family Practice.
2. Doris Rapp, background in pediatric allergy medicine.
3. Al Levin, immunologist. Director of an immunology lab and staff physician at the University of California, San Francisco. Has made connections between low T cells in MCS patients and their symptoms with those of early stage cancer patients.
4. Rebecca Bascom, pulmonary specialist at the University of Maryland School of Medicine in Baltimore. Has researched possible connections between MCS, the trigeminal nerve, and a naturally-occurring protein called substance P.
5. Iris R. Bell, University of Arizona psychiatrist. Has conducted research focusing on the limbic portion of the brain, which regulates our mood and emotions but is also closely connected to the environment through our sense of smell.
6. John Selner, a Denver allergist and respiratory specialist.

See RADETSKY, supra note 11, at 136-158.

[16] See infra notes 344-345 and accompanying text.

[17] Proving injury causation is the paramount barrier that toxic tort plaintiffs need to overcome in the courtroom. SeeJeffrey Trauberman, Statutory Reform of “Toxic Torts”: Relieving Legal, Scientific, and Economic Burdens on the Chemical Victim, 7 HARV. ENVT’L L. REV. 177, 197 (1983); Richard J. Pierce, Encouraging Safety: The Limits of Tort Law and Government Regulation, 33 VAND. L. REV. 1281, 1298 (1980).


[19] Frye v. United States, 293 F. 1013 (D.C. App. 1923). The Frye rule has been commonly known as the “Frye general acceptance” test. See infra notes 125-127 and accompanying text (discussing the Frye rule).

[20] Daubert v. Dow Merrell Pharmaceuticals, Inc., 509 U.S. 579 (1993).

[21] General Electric Co. v. Joiner, 522 U.S. 136 (1997).

[22] The Daubert and Joiner decisions only have full relevance in federal courts, as some states have specifically declined to follow Daubert, and 20 states remain steadfast in their dedication to FryeSee EDWARD J. IMWINKELRIED, THE METHODS OF ATTACKING SCIENTIFIC EVIDENCE 108 (1997).

[23] Seee.g., Schubert v. Nissan Motor Corp. in U.S.A., 148 F.3d 25 (1st Cir. 1998); Kirstein v. Parks Corp., 159 F.3d 1065 (7th Cir. 1998); Moore v. Ashland Chemical Inc., 151 F.3d 269 (5th Cir. 1998); Mitchell v. Gencorp. Inc., 165 F.3d 778 (10th Cir. 1999); Cabrera v. Cordis, 134 F.3d 1418 (9th Cir. 1998); Heller v. Shaw Industries, Inc., 167 F.3d 146 (3d Cir. 1998); Wilson v. Merrell Dow Pharmaceuticals, Inc., 160 F.3d 625 (10th Cir. 1998); Aldridge v. Goodyear Tire & Rubber, No. Civ. H-90-140, 1999 WL 38385 (D.Md. Jan. 28, 1999); Zwillinger v. Garfield Slope Housing Corp., No. CV94-4009(SMG), 1998 WL 623589 (E.D.N.Y. Aug. 17, 1998); Childs v. General Motors Corp., N. CIV. A. 95-0331, 1998 WL 414719 (E.D.Pa. July 22, 1998); In re Conrail Toxic Tort Fela Litig., No. CIV. A94-11J, CIV. A94-4J, 1998 WL 465 897 (W.D.Pa. Aug. 4, 1998); National Bank of Commerce v. Assoc. Milk Producers, Inc., 22F.Supp.2d 942 (E.D.Ark. 1998); Coffin v. Orkin Exterminating Co., Inc., 20 F.Supp.2d 107 (D.Me. 1998); Mercer v. Rockwell Int’l Corp., 24 F.Supp.2d 735 (W.D.Ky. 1998); Old Nat’l Trust Co. v. Korea Iron & Steel Co., 993 F.Supp. 1204 (S.D.Ill. 1998); Belofsky v. General Electric Co., 1 F.Supp.2d 504 (D.V.I. 1998); Pick v. American Med. Systems, Inc., 958 F.Supp. 1151 (E.D.La. 1997).

In contrast, a significantly smaller number of plaintiffs have been successful. See, e.g., Zuchowicz v. United States, 140 F.3d 381 (2d Cir. 1998); Maryland Casualty co., v. Therm-O-Disc, Inc., 137 F.3d 780 (4th Cir. 1998); Kennedy v. Collagen Corp., 161 F.3d 1226 (9th Cir. 1998); Ambrosini v. Labarraque, 101 F.3d 129 (D.C. Cir. 1998); Graham v. Playtex Products, Inc., 993 F.Supp. 127 (S.D.N.Y. 1998).

[24] See, e.g., Zwillinger v. Garfield Slope Housing Corp., N. CV 94-4009 (SMG), 1998 WL 623589 (E.D.N.Y. Aug. 17, 1998) (onset of symptoms was triggered by exposure to offgassing of chemical fumes from new synthetic carpet); Coffin v. Orkin Exterminating Co., 20 F.Supp.2d 107 (D.Me. 1998) (triggering event was exposure to exterminator’s pesticide in office building); Treadwell v. Dow-United Technologies, 970 F.Supp. 974 (M.D.Ala. 1997) (triggering exposure was to epoxy resin in the workplace); Bradley v. Brown, 852 F.Supp. 690 (N.D.Ind. 1994) (triggering event was exposure to pesticide through building’s ventilation system).

[25] See infra Section IIID.

[26] See Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 1001-02 (C.D. Cal. 1995) (discovering through its own research that “every court to rule on this issue” has excluded MCS causation testimony on the grounds that “there is no scientific evidence that such a disease exists”). The reason for this exclusion, however, has not been poor experts or poor methodology, but a lack of general acceptance of MCS or clinical ecologists by the medical and scientific community. See infra Section IVC.


[28] Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 596-97 (1993). The Court added, “Scientific conclusions are subject to perpetual revision. Law, on the other hand, must resolve disputes finally and quickly.”

[29] See EXPERT EVIDENCE: INTERPRETING SCIENCE IN THE LAW 1 (Roger Smith & Brian Wynne, eds. 1989) (hereinafter EXPERT EVIDENCE).

[30] See Brian Wynne, Establishing the Rules of Laws: Constructing Expert Authority, in EXPERT EVIDENCE, supra note 29, at 33 (“It has been accepted in the sociology of science that scientific conflicts offer the most fruitful examination of scientific knowledge in-the-making, because the adversarial pressure forces the premises and conventions of each side out in the open”);

[31] See Moore v. Ashland Chemicals, Inc., 126 F.3d 679, 685 (5th Cir. 1997) (discussing the Daubert decision as relevant to “hard science” or “Newtonian science,” that is, science grounded in the scientific method).

[32] Cf. Allen v. Pennsylvania Engineering Corp., 102 F.3d 194, 198 (5th Cir. 1996) (quoting an expert as saying, “This is not a scientific study. This is a legal opinion”).

[33] See GOLDBERG, supra note 27, at 19: “Scientists looking for empirically verifiable truth have to believe there is some kind of order in their universe, whether it is expressible in traditional cause-and-effect terms or in probabilistic equations;” Sheldon Glashow, Does Ideology Stop at the Laboratory Door? A Debate on Science and the Real World, NEW YORK TIMES, Oct. 22, 1989, at E24:

We believe that the world is knowable, that there are simple rules governing the behavior of matter and the evolution of the universe. We affirm that there are eternal, objective, extrahistorical, socially neutral, external and universal truths and that the assemblage of these truths is what we call physical science. Natural laws can be discovered that are universal, invariable, inviolate, genderless and verifiable. They may be found by men or by women or by mixed collaborations of any obscene proportions. Any intelligent alien anywhere would have come upon the same logical system as we have to explain the structure of protons and the nature of supernovae.

[34] As this discussion will illustrate, scientists who engage in research on unaccepted fields of science, regardless of their adherence to the scientific method, are not recognized as legitimate.

[35] See KENNETH R. FOSTER, & PETER W. HUBER, JUDGING SCIENCE: SCIENTIFIC KNOWLEDGE AND THE FEDERAL COURTS 166 (1997) (quoting physicist John Ziman as saying that science “is never one individual . . . . It is a group of individuals, dividing their labor but continuously and jealously checking each other’s contributions”).


[37] See KUHN, supra note 5, at 6-7.

[38] See id. at 10.

[39] See id. at 176.

[40] See id. at 23.

[41] See id. at 67. But see C. TRUESDELL, GREAT SCIENTISTS OF OLD AS HERETICS IN “THE SCIENTIFIC METHOD” 65-66 (1987) (suggesting that perhaps many of the great scientific revolutions in history had little to no impact on the scientific communities that should have been upset by them).

[42] See KUHN, supra note 5, at 68.

[43] Something is “valid” if it is “well-grounded on principles or evidence; able to withstand criticism or objection, as an argument; sound.” WEBSTER’S NEW WORLD DICTIONARY 1568 (2d College ed. 1970).

[44] See KUHN, supra note 5, at 15.

[45] See FOSTER & HUBER, supra note 35, at 139 (noting that “[l]ogical consistency is the first requirement of scientific validity”). Yet logical validity cannot stand on its own, regardless of its brilliance. It must be supported by concrete, definite statements about cause and effect. See ERNAN MCMULLIN, THE INFERENCE THAT MAKES SCIENCE 5 (1992).

[46] See ROBERT W. HOLT, A HANDBOOK ON THE SCIENTIFIC METHOD 17 (1982) (observing that “[t]heories in astronomy, for example are strong in explanation and prediction of astronomical events, yet by the very nature of the fact that celestial objects are so distant from us these theories do not yet allow for control of astronomical phenomena”).

[47] Karl Popper, A Survey of Some Fundamental Problems, in THE LOGIC OF SCIENTIFIC DISCOVERY 32-33 (1992)

[48] See generally BENJAMIN N. CARDOZO, THE NATURE OF THE JUDICIAL PROCESS (1921) (discussing the myth of absolute objectivity in judicial decision making).

[49] See, e.g., HOLT, supra note 46, at 1 (referring to the process of scientific understanding as “intellectual warfare fought by scientists who are passionate partisans of one theoretical viewpoint or another”); EXPERT EVIDENCE,supra note 29, at 4 (“Scientific knowledge is established, assimilated, and transmitted by social trust and authority, rather than by the radical skeptical testing suggested by science’s dominant public image”). But see Clarr v. Burlington Northern Railway Co., 29 F.3d 499, 503 (9th Cir. 1994) (opining that “scientists whose conviction about the ultimate conclusion of their research is so firm that they are willing to aver under oath that it is correct prior to performing the necessary validating tests [may] properly be viewed by the district court as lacking the objectivity that is the hallmark of the scientific method”).


[51] See RICHARD R. YEO, THE POLITICS AND RHETORIC OF SCIENTIFIC METHOD 262 (1986). In describing what he meant by accessible, single and transferable, Richard Yeo said:

These three characterizations respectively claimed that the method of science could be understood and practised by a large number of people; that there was a single method common to all branches of science; and that this method could be extrapolated from natural science to other subjects.

Id. Yeo adds that these assumptions, which were derived from the work of Francis Bacon in the early nineteenth century, were later abandoned. See id. at 263.

[52] See HOLT, supra note 49, at 5.

[53] See id.

[54] See id.

[55] See id.


[57] See id. at 45.

[58] See WEBSTER’S NEW WORLD DICTIONARY 1570 (2d College ed. 1970).

[59] See HOLT, supra note 49, at 45-55 (identifying these methods of addressing variables, their advantages and disadvantages, and how the four primary methodologies utilize these methods of addressing variables).

[60] See, e.g., E.K. Hardison Seed Co. v. Jones, 149 F.2d 252, 256 (6th Cir. 1945) (stating that to be valid “the sample portion should be of such nature as to be fairly representative”); United States Steel Group v. United States, 96 F.3d 1352, 1366 (Fed. Cir. 1996) (noting that to be reliable a sample must be representative); Cimino v. Raymark Indus. Inc., 751 F.Supp. 649, 664 (E.D.Tex. 1990) (concluding that the sample group must be representative of the group as a whole).


[62] R. BEAGLEHOLE ET AL., BASIC EPIDEMIOLOGY 3 (World Health Organization 1993).

[63] See Hall v. Baxter Healthcare Corp., 947 F.Supp. 1387, 1403 (D. Or. 1996).

[64] See FOSTER & HUBER, supra note 35, at 151.

[65] See Linda A. Bailey et al., Reference Guide on Epidemiologyin REFERENCE MANUAL ON SCIENTIFIC EVIDENCE (hereinafter “REFERENCE MANUAL”) 126 (Federal Judicial Center 1994).

[66] See, e.g., Renaud v. Martin Marietta Corp., 749 F.Supp. 1545, 1554 (D.Colo. 1990), aff’d, 972 F.2d 304 (10th Cir. 1992) (expert testimony excluded due to lack of epidemiological support); Thomas v. Hoffman-La Roche, Inc., 731 F.Supp. 224, 227-28 (N.D.Miss. 1989), aff’d, 949 F.2d 806, cert. denied, 504 U.S. 956 (1992) (indicating that a plaintiff in a prescription drug product liability case must produce “statistically significant epidemiological proof”); In re Agent Orange Prod. Liab. Litig., 611 F.Supp. 1223, 1231 (E.D.N.Y. 1985), aff’d, 818 F.2d 187 (2d Cir. 1987), cert. denied, 487 U.S. 1234 (1988) (referring to epidemiological studies as the “only useful studies having any bearing on causation’); Michael Dore, A Commentary of the Use of Epidemiological Evidence in Demonstrating Cause-In-Fact, 7 HARV. ENVT’L L. REV. 429, 430-31 (1983) (citing cases to support the notion that epidemiological evidence is the most important type of causation evidence when the cause of an illness is unknown). But see In re Joint Eastern & Southern District Asbestos Litig. v. U.S. Mineral Products Co., 52 F.3d 1124, 1133 (2nd Cir. 1995) (remarking that “by its nature, epidemiology is ill-suited to lead a factfinder toward definitive answers”); FOSTER & HUBER, supra note 35, at 154-55 (discussing some of the flaws with epidemiological studies).

[67] See BEAGLEHOLE ET AL., supra note 62, at 38.

[68] See id. at 39, Fig. 3.5.

[69] See Bailey et al., supra note 65, at 134-36.

[70] See BEAGLEHOLE ET AL., supra note 62, at 39.

[71] See Brock v. Merrell Dow Pharmaceuticals, Inc., 874 F.2d 307, 313 (5th Cir. 1989) (stating that epidemiological proof was “the most useful and conclusive type of evidence” but specifically stated that they were not holding that it is a “necessary element in all toxic tort cases”); Pick v. American Medical Systems, Inc., 958 F.Supp. 1151, 1158 (E.D.La. 1997) (disagreeing with the defendant’s position that epidemiological studies are mandated).

[72] Between “cohort studies” and “case control groups,” the latter are considered less reliable by the courts. See, e.g., Hall v. Baxter Healthcare Corp., 947 F.Supp. 1387, 1411 (D. Or. 1996) (“[c]ase reports and case studies are universally regarded as an insufficient scientific basis for a conclusion regarding causation because case reports lack controls”).

[73] See BEAGLEHOLE ET AL., supra note 62, at 36.

[74] See Bailey et al., supra note 65, at 136.

[75] See BEAGLEHOLE ET AL., supra note 62, at 37.

[76] See KENNETH R. FOSTER ET AL., PHANTOM RISKS: SCIENTIFIC INFERENCE AND THE LAW 5 (1994) (hereinafter “PHANTOM RISKS”); Christopher H. Buckley, Jr. & Charles H. Haake, Separating the Scientist’s Wheat from the Charlatan’s Chaff: Daubert’s Role in Toxic Tort Litigation, 28 ENVT’L L. REP. 10293 (June 1998). Relative risk ratios then establish a numerical representation of the likelihood for the occurrence of a disease. See Manko v. United States, 636 F.Supp. 1419, 1434 (W.D.Mo. 1986), aff’d in part and rev’d in part, 830 F.2d 831 (8th Cir. 1987):

A relative risk of “1” is the expected rate of contracting a disease in a population not influenced by the event under investigation. A relative risk of “2” means that the disease occurs among the population subject to the event under investigation twice as frequently as the disease occurs among the population not subject to the event under investigation. Phrased another way, a relative risk of “2” means that, on the average, there is a fifty percent likelihood that a particular case of the disease was caused by the event under investigation and a fifty percent likelihood that the disease was caused by chance alone. A relative risk greater than “2” means that the disease more likely than not was caused by the event.

[77] See BEAGLEHOLE ET AL., supra note 62, at 37.

[78] See Pick v. American Medical Systems, Inc., 958 F.Supp. 1151, 1160-61 (E.D.La. 1997):

Case study populations are frequently small, leaving open the real possibility that the findings are due to chance rather than to exposure to the suspected substance. Another criticism is that the symptoms are often subjective on the part of the patient, susceptible to exaggeration or outright falsity (particularly if litigation is contemplated). Another problem . . . is potential bias. Doctors who specialize in certain conditions . . . attract patients with those symptoms.


[80] See Walter J. Decker, Introduction and History, in HANDBOOK OF TOXICOLOGY 1 (Thomas J. Haley & William O. Berndt eds. 1987) (hereinafter TOXICOLOGY HANDBOOK); Bernard D. Goldstein & Mary Sue Henifin, Reference Guide on Toxicology, in REFERENCE MANUAL, supra note 65, at 185.

[81] “Xenobiotic” agents are manmade or foreign in origin. See generally John A. McLachlan, Functional Toxicology: A New Approach To Detect Biologically Active Xenobiotics, 101 ENVT’L HEALTH PERSP. 386 (Oct. 1993).

[82] See Thomas J. Haley, Clinical Toxicology, in TOXICOLOGY HANDBOOK, supra note 80, at 592.

[83] See Goldstein & Henifin, supra note 80, at 185.

[84] See id.

[85] See id. at 188. But see In re Paoli R.R. Yard Litig., 35 F.3d 717, 743 (3d Cir. 1994) (Paoli II) (observing that while “animal studies may be methodologically acceptable to show that chemical X increases the risk of cancer in animals, [] they may not be methodologically acceptable to show that chemical X increases the risk of cancer in humans”).

[86] See id. at 191.

[87] See Wade-Greaux v. Whitehall Laboratories, Inc., 874 F.Supp. 1441, 1480 (D.V.I. 1994).

[88] See In re Hanford Nuclear Reservation Litig., No. CY-91-3015-AAM, 1998 WL 775340, *9 (E.D. Wash. Aug. 21, 1998); Zwillinger v. Garfield Slope Housing Corp., No. CV 94-4009(SMG), 1998 WL 623589, *17 (E.D.N.Y. Aug. 17, 1998); Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp.2d 942, 978 (E.D.Ark. 1998); Sanderson v. Int’l Fragrances and Flavors, Inc., 950 F.Supp. 981, 995 (C.D.Cal. 1996).


[90] See Mancuso v. Consolidated Edison Co. of New York, 967 F.Supp. 1437, 1445 (S.D.N.Y. 1997).

[91] See Cavallo v. Star Enter., 892 F.Supp. 756, 764 (E.D. Va. 1995), aff’d in relevant part, 100 F.3d 1150, 1159 (4th Cir. 1996).

[92] See Sorensen v. Shaklee Corp., 31 F.3d 638, 644 (8th Cir. 1994)

[93] The criticism of the dependability of toxicology usually revolves around the use of animal studies. Metabolic differences between animals and humans, variations and inconsistencies on how animals and humans react to certain chemicals, as well as different environmental concerns all contribute to the questionable utility of animal studies. SeeSCHRADER-FRECHETTE, supra note 89, at 26; see also Kenneth R. Foster et al., Science and the Toxic Tort, 261 SCIENCE 1509, 1509 (1993) (“High-dose animal studies have questionable relevance to risks to humans from low-dose exposures. Such evidence, presented outside the context of a comprehensive risk assessment, is a gross misuse of scientific data that should be excluded from the courtroom”). But see In re Paoli Railroad Yard PCB Litigation, 35 F.3d 717, 734 (3d Cir. 1994) (reversing a district court’s exclusion of testimony derived from animal studies that were supported by epidemiological data and were used by the EPA to conclude that PCBs were a probable human carcinogen).

[94] See Goldstein & Henifin, supra note 80, at 194 (asserting that “epidemiology and toxicology have much to offer in elucidating the causal relationship between chemical exposure and disease”).

[95] See BEAGLEHOLE ET AL., supra note 62, at 71.

[96] See id.

[97] See id. at 72-73, Figures 5.1 and 5.2 (illustrating risk factors and mechanisms for tuberculosis and cholera).

[98] See id. at 74.

[99] See id.

[100] See supra notes 58-59 and accompanying text.

[101] “Bias” in scientific evidence testimony can be seen through a variety of indicators: skewed, one-sided report testimony; testimony that summarily dismisses or minimizes unexplained variables; testimony that dramatizes or exaggerates; and testimony that relies upon unreliable or unaccepted testing procedures. See R. CHRISTOPHER BARDEN, SCIENCE INTENSIVE LITIGATION: THE EFFECTIVE ANALYSIS AND PRESENTATION OF COMPLEX SCIENTIFIC ISSUES IN THE LEGAL SYSTEM 11 (University of Minnesota Law School 1993).

[102] See BEAGLEHOLE ET AL., supra note 62, at 74 and Fig. 5.3 on 75.

[103] See supra note 76 (discussing numerical significance of “relative risk ratio”).

[104] See Nat’l Bank of Commerce v. Dow Chemical Co., 965 F.Supp. 1490, 1553 (E.D.Ark. 1996); Wade-Greaux v. Whitehall Laboratories, Inc., 874 F.Supp. 1441, 1467 (D.V.I. 1994).

[105] See BEAGLEHOLE ET AL., supra note 62, at 77-81; Jack W. Snyder et al., Injury and Causation on Trial: The Phenomenon of “Multiple Chemical Sensitivities, 2-FALL WIDENER L. SYMP. J. 97, 136 (1997) (listing nine criteria deemed necessary by “the overwhelming majority of scientists, physicians, and epidemiologists” and adding that opinions vary over how many criteria must be met in order to render an opinion regarding causation).

[106] See GOLDBERG, supra note 27, at 14 (observing the difficulties associated with testing a belief that certain types of materials are obscene); cf. Jacobellis v. Ohio, 378 U.S. 184, 197 (1964) (Stevens, J., concurring) (referring to what sort of materials should be considered obscene, Justice Stevens stated, “I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description . . . But I know it when I see it, and the picture involved in this case is not that”).

[107] See GOLDBERG, supra note 27, at 16 (observing that in a murder case a fact finder is less concerned with the actual time that someone was murdered than with who murdered that person).

[108] Judges tend to apply a more liberal definition of “expert” than does the scientific community. See, e.g., In re Paoli Railroad Yard PCB Litigation, 35 F.3d 717, 741 (3rd Cir. 1994) (“We have eschewed imposing overly rigorous requirements of expertise and have been satisfied with more generalized qualifications,” as can be evidenced by a “broad range of knowledge, skills, and training”). The scientific community, however, possesses a rather poor understanding not only of the expert’s role in the courtroom, but judicial scrutiny of their testimony as well. See, e.g., Marcia Angell, Shattuck Lecture – Evaluating the Health Risks of Breast Implants: The Interplay of Medical Science, the Law, and Public Opinion, 334 NEW ENGLAND J. OF MED. 1513, 1516 (1996):

Witnesses are considered experts on the basis of very broadly defined credentials (for example, pathologists may be permitted to testify about epidemiologic questions), and they needn’t produce evidence from the literature to buttress their opinions, even when there are relevant studies in peer-reviewed journals. In the courtroom, their opinions are the evidence. This is a far cry from the scientific method, which accepts no conclusions, no matter whose they are, without evidence (emphasis original).

[109] See THOMAS A. MAUET, TRIAL TECHNIQUES xix (4th ed. 1996).

[110] See Wynne, supra note 30, at 32 (noting that “such procedures sometimes show that ‘established scientific fact’ is riddled with suppositions, unstated limiting conditions, and other qualifications or uncertainties”).

[111] Contrary to the legal understanding+- that it is the plaintiff who must prove causation, arising from the agency relationship that exists between the lawyer and his client, it is ultimately up to the lawyer to make a case for his client. It is this lawyer who must use his knowledge, skill, and command of rules and procedure to prevail in the courtroom.

[112] “But for” causation has been defined as follows: “The defendant’s conduct is a cause of the event if the event would not have occurred but for that conduct; conversely, the defendant’s conduct is not a cause of the event if the event would have occurred without it.” PROSSER & KEATON, TORTS, § 41, at 266 (Lawyer’s 5th ed. 1984). See alsoRICHARD A. EPSTEIN, CASES AND MATERIALS ON TORTS 468 (6th ed. 1995).

[113] See generally New York Central R.R. v. Grimstad, 264 F. 334 (2d Cir. 1920); Richardson v. Richardson-Merrell, 649 F.Supp. 799 (D.D.C. 1986); Stimpson v. Wellington Service Corp., 246 N.E.2d 801 (Mass. 1969) (each discussing the essential elements of cause-in-fact causation).

[114] See EPSTEIN, supra note 112, at 467.

[115] Proximate cause is a “significant hurdle” that plaintiffs seeking recovery in tort for an occupational disease must face. See Aldridge v. Goodyear Tire & Rubber Co., No. Civ. H-90-140, 1999 WL 38385, at *7 (D. Md. Jan. 28, 1999).

[116] See EPSTEIN, supra note 112, at 468.

[117] See Snyder et al., supra note 105, at 139.

[118] See id. at 140.

[119] Id. at 139.

[120] See, e.g., Raynor v. Merrell Pharmaceuticals Inc., 104 F.3d 1371 (D.C.Cir. 1997); Jenson v. Eveleth Taconite Co., 130 F.3d 1287 (8th Cir. 1997); Cali v. Danek Medical, Inc., 24 F.Supp.2d 941 (W.D.Wis. 1998); Treadwell v. Dow-United Technologies, 970 F.Supp. 974 (M.D.Ala. 1997); Higgins v. Diversey Corp., 998 F.Supp. 598 (D.Md. 1997); Arnold v. Riddell, Inc., 882 F.Supp. 979 (D.Kan. 1995).

[121] This is the most prominently used causation evidence threshold, having been used by 120 federal cases that applied the Daubert standard. See, e.g., Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311 (9th Cir. 1995); In re Paoli R.R. Yard PCB Litig., 35 F.3d 717 (3d Cir. 1994); Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp.2d 942 (E.D.Ark. 1998); In re Breast Implant Litigation, 11 F.Supp.2d. 1217 (D.Colo. 1998); Nat’l Bank of Commerce v. Dow Chemical Co., 965 F.Supp. 1490 (E.D.Ark. 1996); Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981 (C.D.Cal. 1996); Casey v. Ohio Medical Products, 877 F.Supp. 1380 (N.D.Cal. 1995).

[122] See, e.g. Hulmes v. Honda Motor Co., 960 F.Supp. 844 (D.N.J. 1997); Gess v. United States, 952 F.Supp. 1529 (M.D.Ala. 1996); Bennett v. PRC Public Sector, Inc., 931 F.Supp. 484 (S.D.Tex. 1996); Diaz v. Johnson Matthey, Inc., 893 F.Supp. 358 (D.N.J. 1995).

[123] See Snyder et al., supra note 105, at 140.

[124] See Erin K. L. Mahaney, Assessing the Fitness of Novel Scientific Evidence in the Post-Daubert EraPesticide Exposure Cases as a Paradigm for Determining Admissibility, 26 ENVT’L L. 1161, 1179 (1996).

[125] 293 F. 1013 (D.C. Cir. 1923).

[126] Id. at 1014.

[127] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 585 (1993).

[128] See, e.g., HUBER, supra note 18, at 96 (bemoaning the “eroding” rules of evidence and the “junk science” they permit into the courtroom); PHANTOM RISKS, supra note 76, at 38-39 (saying that “[f]or half a century, the Frye rule served reasonably well to exclude unreliable or eccentric scientific evidence from the courtroom” and blaming the introduction of the Federal Rules of Evidence for an “avalanche of questionable testimony on scientific issues in the courtroom”).

[129] See Berger, supra note 159, at 107.

[130] See Angell, supra note 108, at 1516.

[131] HUBER, supra note 18, at 3.

[132] See PHANTOM RISKS, supra note 76, at 28; see also HUBER, supra note 18, at 2:

Maverick scientists shunned by their reputable colleagues have been embraced by lawyers. Eccentric theories that no respectable government agency would ever fund are rewarded munificently by the courts. Batteries of meaningless, high-tech tests that would amount to medical malpractice or insurance fraud if administered in a clinic for treatment are administered in court with complete impunity by fringe experts hired for litigation. The pursuit of truth, the whole truth, and nothing but the truth has given way to reams of meaningless data, fearful speculation, and fantastic conjecture.

[133] See id. at 35.

[134] See id. at 32-34.

[135] Id. at 38. See also E. Donald Elliott, Toward Incentive-Based Procedure: Three Approaches for Regulating Scientific Evidence, 69 B.U.L.REV. 487, 492 n.22 (1989) (“Our reliance on lay juries to assess the credibility of technical experts is not a problem, of course, if one is willing to assume that something magical happens in the jury room so that ordinary people can suddenly unravel complex technical and scientific issues that would baffle the rest of us”); PHANTOM RISKS, supra note 76, at 37-38 (“Often baffled by weeks or months of complex scientific testimony, jurors may be left to rely on their instincts, ‘common sense,’ sense of justice . . . [and] are not equipped to sort out the complex scientific issues that arise in hazardous exposure cases”).

[136] See Angell, supra note 108, at 1517.

[137] Once again, herein lies another illustrative opportunity regarding the differences between science and the law. Science seeks to find the “truth.” The Law seeks justice. The two are not necessarily complimentary.

[138] See Angell, supra note 108, at 1513-16.

[139] See, e.g., HUBER, supra note 18, at 219-20 (discussing instances where a “certain brand of psychiatric soothsaying,” that is, the ability to use psychiatry to predict “future dangerousness” of a criminal defendant, while rejected by the American Psychiatric Association, has been accepted by the courts).

[140] See PHANTOM RISKS, supra note 76, at 28-31.

[141] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 596-97 (1993) (addressing concerns raised by both petitioners and respondents regarding potential for abuse through abandoning the Frye “general acceptance” test and providing a screening role to judges that might stifle or repress scientific ingenuity).

[142] For the purpose of this discussion, “bad” refers either to experts who do not support their testimony with acceptable methodology or who perform poorly in presenting their testimony.

[143] 509 U.S. 579 (1993).

[144] Id. at 590.


[146] The Supreme Court held that this test was superceded by the Federal Rules of Evidence. See Daubert, 509 U.S. at 587.

[147] This concession to the scientific establishment’s conservative branch has been criticized as “perpetuat[ing] the judicial system’s close-mindedness towards novel scientific theories.” Jeffry D. Cutler, Comment, Implications of Strict Scrutiny of Scientific Evidence: Does Daubert Deal a Death Blow to Toxic Tort Plaintiffs?, 10 J. ENVT’L L. & LITIG. 189, 211 (1995) (arguing that the Supreme Court’s description of what constitutes scientific method “seems to be drawn primarily from amicus briefs in the case filed by established scientific institutions” at n.119).

[148] See id. at 593 (quoting C. HEMPEL, PHILOSOPHY OF NATURAL SCIENCE 49 (1966)).

[149] See id. (quoting KARL POPPER, CONJECTURES AND REFUTATIONS: THE GROWTH OF SCIENTIFIC KNOWLEDGE 37 (5th ed. 1989) (“[T]he criterion of the scientific status of a theory is its falsifiability, or refutability, or testability”)).

[150] Whether a plaintiff’s expert was seeking to testify regarding valid scientific knowledge is only one element of theDaubert decision. The expert’s opinion must also be reliable, relevant, helpful, and “fit” the facts of the case. See infraSection IIIB.

[151] See id. In order to meet the peer review and publication requirement, it is the underlying theory that needs to be subject to peer review, not the specific scientist or doctor. It is the theory, not the person, that constitutes “science.”See Kannankeril v. Terminix Int’l, Inc., 128 F.3d 802, 809 (3rd Cir. 1997) (observing that the since the effects of organophosphates on humans was well documented, it was not necessary that the plaintiff’s witness himself had published any articles on the theory); see also Pick v. American Medical Systems, 958 F.Supp. 1151, 1158 n.19 (E.D. La. 1997):

True peer review means that a scientific hypothesis is subjected to independent evaluation by other scientists in that particular field, typically by independent testing and replication of the results. Pre-publication “editorial peer review,” on the other hand, usually consists of sending the proposed article to several outside reviewers who comment on its content and make a recommendation on publication. It is simply not feasible for the editorial staff or the outside reviewers to attempt to replicate the author’s findings prior to publishing them. Consequently, just because an article is published in a prestigious journal, or any journal at all, does not mean per se that it is scientifically valid. (citation omitted)

But see FOSTER & HUBER, supra note 35, at 157:

Some papers are brilliant, others are junk. Most scientific papers, once published, are never cited and are quickly forgotten. The scientific literature is full of inaccurate data, conjectures that turn out to be incorrect, and theories that lead nowhere. Many studies are like fishing expeditions: the scientist tries something to see what happens, planning an experiment on a conjecture or on no theory at all.

[152] See id.

[153] See id. (citing Horrobin, The Philosophical Basis of Peer Review and the Suppression of Innovation, 263 J. AM. MED. ASS’N 1438 (1990)).


[155] See id. at 593-94 (in addition, the Court noted that “[s]ome propositions … are too particular, too new, or of too limited interest to be published”); cf. Southland Sod Farms v. Stover Feed Co., 108 F.3d 1134, 1142 (9th Cir. 1997) (adding that “even if the tests were not conducted independently or subjected to peer review, these are only two of the ways Plaintiffs can demonstrate admissibility”).

[156] See Daubert, 509 U.S. at 594 (citing United States v. Smith, 869 F.2d 348, 353-54 (7th Cir. 1989) (surveying studies of the error rate of spectrographic voice identification techniques)).

[157] See Allen v. Pennsylvania Engineering Corp., 102 F.3d 194, 197 (5th Cir. 1996) (holding that mere “suggestiveness” is not only statistically insignificant, it is inadequate to support a causal connection).

[158] McClelland v. Goodyear Tire & Rubber Co. , 735 F.Supp. 172, 174 (D. Md. 1990).

[159] Margaret A. Berger, Evidentiary Framework, in REFERENCE MANUAL, supra note 65, at 82.

[160] See KUHN, supra note 5, at 185.

[161] Id. (quoting United States v. Williams, 583 F.2d 1194, 1198 (2nd Cir. 1978) (noting professional organization’s standard regarding spectrographic analysis)).

[162] See Berger, supra note 159, at 83 (referring to the legal experience with Thalidomide). But see American Academy of Allergy and Immunology, Position Statement: Clinical Ecology, 78 J. ALLERGY CLIN. IMMUNOL. 269, 270 (Aug. 1986) (hereinafter “AAAI Position Statement”) (“Anecdotal articles do not constitute sufficient evidence of a cause-and-effect relationship between symptoms and environmental exposure”).

[163] Id.

[164] 753 F.2d 1224 (3rd Cir. 1985).

[165] The Third Circuit was reviewing a district court’s decision that ruled such testimony was inadmissible because such testimony could never meet the “helpfulness” standard of Rule 702. The Third Circuit disagreed, but ruled that such admission was not automatic but conditional. See Downing, 753 F.2d at 1226.

[166] See Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 594 (1993).

[167] See Downing, 753 F.2d at 1238. See also supra note 146 (discussing Frye “general acceptance” test).

[168] Downing, 753 F.2d at 1238. On remand in Daubert, the Ninth Circuit added that the methodology must constitute “the scientific method, as it is practiced by (at least) a recognized minority of scientists in their field.” Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311, 1319 (9th Cir. 1995).

[169] See id. In discussing the reliability of novel scientific evidence and the reliability of its technique, the court inDowning “join[ed] a growing number of courts that have focused on reliability as a crucial element of admissibility” under Rule 702. Id. (citing several state cases for support). [170] Id. While this language in the Downing decision was not specifically adopted in Daubert (unlike the “reliability assessment” language), it is in keeping with the “flexible” approach the Daubert decision requires.

[171] See id.

[172] Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 594-95 (1993). See also In re Paoli R.R. Yard Litig., 35 F.3d 717, 744 (3rd Cir. 1994) (Paoli II) (noting that a “judge will often think that an expert has good grounds to hold the opinion that he or she does even though the judge thinks that the opinion is incorrect”). The Third Circuit added:

The grounds for the expert’s opinion merely have to be good, they don’t have to be perfect (emphasis added). The judge might think that there are good grounds for an expert’s conclusion even if the judge thinks that there are better grounds for some alternative conclusion, and even if the judge thinks that a scientist’s methodology has some flaws such that if they had been corrected, the scientist would have reached a different result.

Id. This conclusion-methodology question is one that has been fiercely debated, but inadequately answered. See Jay P. Kesan, Note, An Autopsy of Scientific Evidence in a Post-Daubert World, 84 GEO. L.J. 1985, 2019 n.218 (1996).

[173] See id. at 596 (adding that a judge can issue a directed verdict for summary judgment “in the event the trial court concludes that the scintilla of evidence presented supporting a position is insufficient to allow a reasonable juror to conclude that the position more likely than not is true”).

[174] See Berger, supra note 159, at 88.

[175] 509 U.S. 579 (1993).

[176] See Joseph Sanders, The Bendectin Litigation: A Case Study in the Life Cycle of Mass Torts, 43 HASTINGS L.J. 301, 317-18 (1992) (observing that the issue of a connection between Bendectin and the occurrence of birth defects in the fetuses of mothers who ingested the drug was first raised in 1969).

[177] See supra notes 132-134 (discussing Frye “general acceptance” test).

[178] Daubert, 509 U.S. at 588.

[179] The primary focus of the Daubert decision was the definition of scientific knowledge for purposes of a Rule 702 admissibility inquiry. See Daubert, 509 U.S. at 588-94.

[180] See id. at 589.

[181] IdCf. Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 996 (C.D. Cal. 1996) (“Plausibility does not equal reliability; only ‘objective, independent validation’ equals reliability”).

[182] See Daubert, 509 U.S. at 590. The “reliability” inquiry of the Daubert standard consists of the four elements discussed supra Section IIIA. Reliability should not, however, be the ultimate basis for excluding expert testimony. As the Third Circuit indicated in Paoli I, “the reliability requirement must not be used as a tool by which the court excludes all questionably reliable evidence.” In re Paoli R.R. Yard PCB Litig., 916 F.2d. 829, 857 (3rd Cir. 1990). The “ultimate touchstone is helpfulness to the trier of fact, and with regard to reliability, helpfulness turns on whether the expert’s ‘technique or principle [is] sufficiently reliable so that it will aid the jury in reaching accurate results.'” DeLuca v. Merrell Dow Pharmaceuticals, Inc., 911 F.2d 941, 956 (3rd Cir. 1990) (quoting 3 J. WEINSTEIN & M. BERGER, WEINSTEIN’S EVIDENCE 702[03], at 702-35 (1988)). A judge frequently should find an expert’s methodology helpful “even when the judge thinks that the expert’s technique has flaws sufficient to render the conclusions inaccurate.” In re Paoli R.R. Yard PCB Litig., 35 F.3d 717, 744-45 (3rd Cir. 1994) (Paoli II).
In Paoli II, the Third Circuit combined the four Daubert reliability factors with those of a previous case, United States v. Downing, 753 F.2d 1224 (3rd Cir. 1990), to formulate an expanded set of factors:

(1) whether a method consists of a testable hypothesis; (2) whether the method has been subject to peer review; (3) the known or potential rate of error; (4) the existence and maintenance of standards controlling the technique’s operation; (5) whether the method is generally accepted; (6) the relationship of the technique to methods which have been established to be reliable; (7) the qualifications of the expert witness testifying based on the methodology; and (8) the non-judicial uses to which the method has been put.

Paoli II, 35 F.3d at 742 n.8. The Third Circuit incorporated the previous Downing factors because the Supreme Court’sDaubert decision “specifically refuse[d] to disavow any of the particular factors” listed in DowningId. at 742 (citing Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 595 n.12 (1993)). These eight factors have been referred to as “the Daubert-Paoli factors.” Diaz v. Johnson Matthey, Inc., 983 F.Supp. 358, 373 (D.N.J. 1995).

[183] See Cutler, supra note 147, at 214-15; Jean Macchiaroli Eggen, Toxic Torts, Causation, and Scientific Evidence After Daubert, 55 U. PITT. L. REV. 889, 923 (1994).

[184] One federal district court applying Daubert also conducted a relevancy inquiry under Rule 401. See Pick v. American Medical Systems, Inc., 958 F.Supp. 1151, 1162 (E.D.La. 1997) (“Rule 401 mandates a liberal view of relevancy – evidence having ‘any tendency’ to prove or disprove a fact is admissible”).

[185] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579,591 (1993).

[186] See id. (quoting 3 J. WEINSTEIN & M. BERGER, WEINSTEIN’S EVIDENCE & 702[02], 702-18. To illustrate how evidence might not be relevant to a case, the Court stated:

The study of the phases of the moon, for example, may provide valid scientific “knowledge” bout whether a certain night was dark, and if darkness is a fact in issue, the knowledge will assist the trier of fact. However (absent credible grounds supporting such a link), evidence that the moon was full on a certain night will not assist the trier of fact in determining whether an individual was unusually likely to have behaved irrationally on that night.

[187] See id. at 591-92.

[188] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311, 1320-22 (9th Cir. 1995) (rejecting testimony because experts were unable to prove that defendant’s products “actually caused plaintiff’s injuries” or, at least, that such exposure “more than doubled” plaintiff’s risk of suffering those injuries).

[189] See Cutler, supra note 147, at 191 (stating that “the supposed ‘liberalization’ of the standard for admissibility of evidence actually allows the courts to make recovery less available for toxic tort plaintiffs”).

[190] See Daubert, 509 U.S. at 589, n.7, 600 (declaring that a federal judge must exercise a “gatekeeping responsibility” to insure that admitted scientific testimony is both relevant and reliable).

[191] See id. at 595. Not discussed in this paper is the court’s reminder to judges of their discretion to procure experts under Rule 706. See id. Some of the critics of courtroom use of scientific expert testimony have urged courts to exercise this discretion more often. See Foster et al., supra note 93, at 1614 (adding that “European judges routinely summon their own experts”).

[192] Federal Rule of Evidence 703 states:

The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by the experts in the particular field in forming opinions or inferences upon the subject, the facts or data need not be admissible in evidence.

[193] See Daubert, 509 U.S. at 595. Prior to Daubert, some confusion existed as to how a court should determine what is “reasonably relied upon.” Those who supported a more “liberal” approach to the Federal Rules sought an expanded admissibility of expert testimony, while those who supported a more “conservative” approach advocated a preliminary screening of evidence under Rule 104(a). See Berger, supra note 159, at 107.

[194] See Moore v. Ashland Chemical, Co., 126 F.3d 679, 690 (5th Cir. 1997).

[195] FED. R. EVID. 703, Advisory Committee’s Note.

[196] See United States v. Harper, 802 F.2d 115, 121 (5th Cir.1986).

[197] See United States v. Williams, 447 F.2d 1285, 1290 (5th Cir.1971), cert. denied, 405 U.S. 954 (1972), reh’g denied, 405 U.S. 1048 (1972).

[198] See Berger, supra note 159, at 105.

[199] See Claar v. Burlington Northern R.R. Co., 29 F.3d 499, 500-01 (9th Cir. 1994); In re Breast Implant Litig., 11 F.Supp.2d 1217, 1240 (D.Colo. 1998); Kelley v. American Heyer-Schulte Corp. 957 F.Supp. 873, 883 (W.D.Tex. 1997); see also Berger, supra note 159, at 107-111 (identifying four distinct circumstances where court’s have excluded testimony under Rule 703: (1) Expert’s failure to consider data that must be taken into account; (2) Expert’s reliance on data that should not be taken into account; (3) Expert’s reliance upon data that are erroneous; and (4) Expert’s opinion does not rest on a foundation that experts would generally find reliable).

[200] See id. at 111.

[201] Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 592 (1993).

[202] See id. at 592 n.10 (citing Bourjaily v. United States, 483 U.S. 171, 175-76 (1987)); see also supra note 122 (citing several cases that applied this standard).

[203] See, e.g., In re Paoli R.R. Yard PCB Litig., 35 F.3d 717, 738-39 (3d Cir. 1994) (Paoli II); Bishop v. General Motors Corp., No. CIV-94-286-B, 1995 WL 886817 (E.D.Okla. Aug. 18, 1995); Gier v. Educational Service Unit No. 16, 845 F.Supp. 1342 (D.Neb. 1994).

[204] See Daubert, 509 U.S. at 595 (quoting Rule 403). This application to a Daubert inquiry would not be appropriate, however, in the case of a bench trial. See Gulf State Util. Co. v. Ecodyne Corp., 635 F.2d 517, 519-20 (5th Cir. 1981) (holding that the weighing process of Rule 403 “has no logical application to bench trials”).

[205] See Berger, supra note 159, at 114-17.

[206] General Electric Co. v. Joiner, 118 S.Ct. 512, 520 (1997) (Breyer, J. concurring).

[207] 118 S.Ct. 512 (1997).

[208] Id. at 516.

[209] See id. at 518.

[210] See id. at 517.

[211] See id.

[212] Id.

[213] See id. at 519:

[N]othing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence which is connected to existing data only by the ipse dixit of the expert. A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered.

[214] See Steve Gold, Note, Causation in Toxic Torts: Burdens of Proof, Standards of Persuasion, and Statistical Evidence, 96 Yale L. J. 376, at 376 n.1 (1986).

[215] See id.

[216] See Gold, supra note 214, at 376-77 (explaining that “proving the cause of injuries that remain latent for years…is the ‘central’ problem for toxic tort plaintiffs”).

[217] This is certainly the case with MCS. See infra Section VB.

[218] A sublime illustration of the scrutiny that the Supreme Court’s decision in Daubert generates can be seen in the Ninth Circuit’s decision in Daubert on remand:

Yet something doesn’t become “scientific knowledge” just because it’s uttered by a scientist; nor can an expert’s self-serving assertion that his conclusions were “derived by the scientific method” be deemed conclusive, else the Supreme Court’s decision could have ended with a footnote or two . . . [T]herefore, though we are largely untrained in science and certainly no match for any of the witnesses whose testimony we are reviewing, it is our responsibility to determine whether those experts’ proposed testimony amounts to “scientific knowledge,” constitutes “good science,” and was “derived by the scientific method.”

Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311, 1315-16 (9th Cir. 1995).

[219] FED. R. CIV. PRO. 702 provides, in part, that “a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify” about scientific issues in the form of an opinion.

[220] See, e.g., Diaz v. Johnson Matthey, Inc., 893 F.Supp. 358, 372 (D.N.J. 1995) (observing that expert “knew little about” etiology of disease, had only casually studied the literature, even only skimming some of them, and was unable to testify about the contents of literature without constantly referring to it); Wade-Greaux v. Whitehall Labs., Inc., 874 F.Supp. 1441, 1476 (D. Vi. 1993), aff’d without opinion, 46 F.3d 1120 (3d Cir. 1994) (stating that expert was unqualified to testify because he had merely reviewed selected articles on the relevant subject for purposes of litigation).

[221] See, e.g., Mancuso v. Consolidated Edison Co. of New York, 967 F.Supp. 1437, 1443 (S.D.N.Y. 1997) (holding that internist possessed neither the training nor experience necessary for him to testify regarding the effect of PCBs on living creatures).

[222] See Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp.2d 942, 969 (E.D.Ark. 1998) (recalling expert’s testimony that he was not qualified to testify to dose response curve necessary to prove causation); Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 993 (C.D.Cal. 1996) (choosing a neuropsychologist who has no training in medicine, toxicology, or chemistry to testify regarding causation of various maladies that have a toxic or chemical trigger).

[223] See Pick v. American Medical Systems, Inc., 958 F.Supp. 1151, 1162 (E.D.La. 1997) (testifying that the linkages the plaintiff was suggesting between silicone penile implants and breast implants was “so different that any comparison between the two was illogical and irrelevant”).

[224] See, e.g., Nat’l Bank of Commerce, 22 F.Supp.2d at 951-52 (E.D.Ark. 1998) (“[T]he Court finds that there is no scientific literature drawing a direct connection between the inhalation of vapors containing AFM . . . and the occurrence of laryngeal cancer in humans”); Sanderson, 950 F.Supp. at 994 (noting that plaintiff’s expert could not make a showing that published work supported causation theory because no such publication existed).

[225] See, at 997 (citing a study that expressly stated that “it is impossible to extrapolate from this study to human exposures”).

[226] See Aldridge v. Goodyear Tire & Rubber Co., No. Civ. H-90-140, 1999 WL 38385, at *13 (D. Md. Jan. 28, 1999) (declaring that references to the “‘knowledge of the scientific literature’ standing alone do little to satisfy the reliability requirement”).

[227] See, e.g., Sanderson, 950 F.Supp. at 995 (applying a methodology so obscure that, as far as the court could tell, the expert “simply made it up”).

[228] See id. at 999-1000 (being unable to articulate statistical probability and admitting that not published statistics would allow him to quantify his estimate, leading the court to correctly conclude, “This is not a ‘scientific connection'”).

[229] See Cavallo v. Star Enter., 892 F.Supp. 756, 771 (E.D.Va. 1995), aff’d in relevant part, 100 F.3d 1150, 1159 (4th Cir. 1996) (“Courts have held that even if an expert seeking to testify is not a toxicologist, he must employ principles and methods of toxicology if he is to give an opinion on an issue relating to that specialty”).

[230] See, e.g., Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp.2d 942, 968 (E.D.Ark. 1998) (excluding testimony of an expert who admitted to relying “on a general impression that I have and not on toxicologic or scientific method that I can refer to”).

[231] See id. at 984 (observing that none of the plaintiff’s experts conducted their research independent of litigation).

[232] See id. at 966 (failing to identify dosage level that would cause cancer in humans, ignoring other potential causes of the illness, and relying solely on a temporal connection).

[233] See, e.g., id. at 970 (catching an expert’s attempt to use a study that shows a statistically significant increase in the occurrence of a disease as a result of exposure to defendant’s chemical; except the study applied to a disease other than one claimed by the plaintiff). See also id. at 973 (refusing to allow expert to claim that risk factors for another disease would also be similar to risk factors that could cause plaintiff’s disease; once again attempting to analogize to an illness entirely distinct from plaintiff’s).

[234] See Sanderson, 950 F.Supp. at 955.

[235] See, e.g., General Electric Co. v. Joiner, 118 S.Ct. 512, 516 (1997) (remarking that since plaintiff had been a smoker for eight years, had parents who were smokers, and that there was a history of lung disease in the family, the plaintiff was “perhaps already at a heightened risk of developing lung cancer eventually”).

[236] See, e.g.Sanderson, 950 F.Supp. at 995 (“Perhaps because she cannot meet its requirements, plaintiff does not even cite Daubert on remand or the Supreme Court’s decision in Daubert” . . . invoking a test made up entirely by her expert).

[237] See id. at 999 (testifying at first that the exposure “most likely” caused the illness, then later recanting and admitting that he couldn’t say what the cause of her illness was).

[238] See Aldridge v. Goodyear Tire & Rubber Co., No. Civ. H-90-140, 1999 WL 38385, at *8 (D. Md. Jan. 28, 1999) (remarking that a plaintiff’s expert had changed his scientific opinion to meet deficiencies in plaintiff’s proof described in other litigation).

[239] See, e.g., Mancuso v. Consolidated Edison co. of New York, 967 F.Supp. 1437, 1443-44 (S.D.N.Y. 1997) (noting that despite expert’s testimony that “he had read 40 or 50 articles over the course of fifteen years before authoring his initial opinion, and that he subsequently performed approximately 14-15 hours of library research and review before authoring his supplemental opinion and appearing for his deposition,” the expert was unable to answer any questions about what level of PCB contamination was hazardous to humans).

[240] See, e.g., Claar v. Burlington Northern Railroad Co., 29 F.3d 499, 502 (9th Cir. 1994) (observing that toxicology sections of an affidavit, which discussed literature regarding illnesses caused by certain chemicals, “fail[ed] to discuss the majority of the medical conditions alleged by plaintiffs”); Sanderson, 950 F.Supp. at 996 (relying on Claarlanguage to similarly hold expert’s scientific evidence unreliable).

[241] 140 F.3d 381 (2d Cir. 1998).

[242] Ms. Zuchowicz died prior to completion of the suit and her husband, Steven, continued the case on behalf of his wife’s estate. See id. at 383.

[243] 28 U.S.C. §§ 1346(b), 2671-2680 (1994).

[244] See Zuchowicz, 140 F.3d at 383.

[245] While the FDA approved Danocrine for doses no greater than 800 mg/day, Ms. Zuchowicz received 1600 mg/day. The plaintiff’s expert conceded that no formal studies on the effects of Danocrine at such high doses had ever been performed and that very few women had ever received doses this high in any setting. See id. at 385.

[246] See id.

[247] See id. at 385.

[248] See id.

[249] See id. at 386.

[250] See id.

[251] See id. at 387.

[252] General Electric Co. v. Joiner, 118 S.Ct. 512, 517 (1997).

[253] McCullock v. H.B. Fuller Co., 61 F.3d 1038 (2nd Cir. 1995).

[254] Zuchowicz v. United States, 870 F.Supp. 15, 18 (D. Conn. 1994). The Second Circuit impliedly agreed with the district court’s assessment of their qualifications by merely reciting them without further discussion. The Second Circuit’s account of the expert’s qualifications is as follows:

Dr. Richard Matthay is a full professor of medicine at Yale and Associate Director and Training director of Yale’s Pulmonary and Critical Care Section. He is a nationally recognized expert in the field of pulmonary medicine, with extensive experience in the are of drug-induced pulmonary diseases…Dr. Randall Tackett is a tenured, full professor of pharmacology and former department chair from the University of Georgia. He has published widely in the field of the effects of drugs on vascular tissues.

Id. at 385-86.

[255] See id. at 386-87 (“The [Supreme Court in Daubert] emphasized, however, that [the four factors] were not an exclusive or dispositive list of what should be considered, and that the trial court’s inquiry should be a flexible one” (quoting Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579, 594 (1993)). The Zuchowicz court also found a similarly flexible approach in the Second Circuit’s McCullock decision. See id. at 387, saying:

With regard to the doctor’s testimony [in McCullock], we noted that the doctor based his opinion on a range of factors, including his care and treatment of [the plaintiff]; her medical history . . .; pathological studies; . . . his training and experience; use of scientific analysis known as differential etiology (which requires listing possible causes, then eliminating all causes but one); and reference to various scientific and medical treatises.

(quoting McCullock, 61 F.3d at 1044).

[256] See id.

[257] Id.

[258] See generally JONATHAN HARR, A CIVIL ACTION (1995).

[259] Cf. HUBER, supra note 18, at 104 (opining that “clinical ecology is medical fantasy, not fact”).

[260] Compare AMERICAN COUNCIL ON SCIENCE AND HEALTH, MCS: MULTIPLE CHEMICAL SENSITIVITY 27 (concluding that multiple chemical sensitivity is scientifically unsupported, unrecognized by the mainstream medical community and largely based on “junk” science), and HUBER, supra note 18, at 2, with WILLIAM J. REA, CHEMICAL SENSITIVITY: PRINCIPLES AND MECHANISMS (1992) (providing a detailed model supporting the theory of multiple chemical sensitivity), and Linda Lee Davidoff, Multiple Chemical Sensitivities, AMICUS J., Fall 1989, at 12 (discussing the possibility that multiple chemical sensitivity is widely prevalent).

[261] See Suzanne Orofino Galbato, Note, Multiple Chemical Sensitivities: Does Daubert v. Merrell Dow Pharmaceuticals, Inc. Warrant Another Look at Clinical Ecology?, 48 Syracuse L. Rev. 261, 282 (1998) (claiming that clinical ecologists invented MCS, which is “more a belief system than a scientific study”).

[262] See Ephraim Kahn & Gideon Letz, Clinical Ecology: Environmental Medicine or Unsubstantiated Theory, 111 ANNALS INT. MED. 104, 105 (July 15, 1989) (warning that “the practice of ‘environmental medicine’ cannot be considered harmless”).

[263] See HUBER, supra note 18, at 25 (also known as “pathological science” or “the science of things that aren’t so”).

[264] Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 595 (1993) (citing concerns expressed by the respondents in the case that in abandoning the Frye “general acceptance” test, the Supreme Court would create a free-for-all of junk science that would confuse juries). Mainstream “normal” science advocates are historically intolerant of new theories proposed by others, see KUHN, supra note 5, at 24, but this skepticism rarely translates into such virulent disgust. Others offer a more optimistic view of mainstream science than that proposed by Thomas Kuhn.See, e.g., Patricia E. Lin, Note, Opening the Gates to Scientific Evidence in Toxic Exposure Cases: Medical Monitoring and Daubert, 17 REV. LITIG. 551, 570 (1998):

The scientific community simultaneously seeks to encourage innovative thinking and to assure that new ideas are subjected to rigorous review. On the one hand, science is a creative process, in which advances occur only in researchers are encouraged to develop and test innovative ideas . . . On the other hand, because science is a cumulative endeavor in which each scientist must build on the work of others, the scientific community needs to weed out false ideas. (footnote omitted)

[265] Compare A. R. REES & H. J. PURCELL, DISEASE AND THE ENVIRONMENT 141 (1982) (citing common attributes assigned to MCS patients, such as “neurotic,” “pochondriac,” “overanxious,” obsessional,” “paranoid,” and that the illness is all in the patients’ minds), with DOWER, supra note 8, at 134-35 (observing that the terms “neurosis” or “compulsive neurosis” where commonly associated with describing the Japanese psyche, that it was generally believed the Japanese were “collectively ill in a clinical sense”). As the comparison with the Japanese propaganda war illustrates, these are not terms associated with objective science, but a deep-seeded hatred for the targets of such language. Great strides have been made in “proving” the psychological nature of MCS, see, e.g., Carroll M. Brodsky, “Allergic to Everything“: A Medical Subculture, 24 PSCYCHOSOMATICS 731 (1983), but few efforts have been made to sort out the anecdotes from the science, to determine if the psychoses preceded the illness or resulted from prolonged association with the illness. One case study suggested that psychological stress did not predate the onset of MCS symptoms. See Gregory E. Simon et al., Immunologic, Psychological and Neuropsychological Factors in Multiple Chemical Sensitivity: A Controlled Study, 19 AMERICAN COLLEGE OF PHYSICIANS 97, 100 (1993). The study, however, has been greatly criticized for its questionable methodology, its inherent biases, and its funding from the Boeing Company. See generally Controversy Over Multiple Chemical Sensitivities, 120 ANNALS OF INTERNAL MED. 249 (1994) (publishing several editorials by various practitioners).

[266] Northern Exposure: Blowing Bubbles (CBS television broadcast, Nov. 2, 1992). In this particular episode, Dr. Joel Fleischman, a “virtually Board-certified physician,” ridicules MCS patient Mike Monroe, the “Bubble Man,” who has moved into a geodesic dome in order to protect himself from the toxicity of the environment. Cf. Michael I. Luster et al., Chemical Pollutants and “Multiple Chemical Sensitivities”, in PHANTOM RISKS, supra note 76, at 389 (suggesting that many of the symptoms associated with MCS can be treated with psychotherapy).

[267] See REES & PURCELL, supra note 265, at 137, 141 (observing that those who suffer maladies resulting from an adverse reaction to the environment suffer a condition that may “contribute to, or constitute, a form of social deviance” and citing several examples where MCS sufferers were referred to as “antisocial, naughty, badly behaved, unsocial, drunk”).

[268] See id. at 138-43. In addition, most physicians are inadequately trained to properly recognize environmental or occupational illnesses in general, let alone something as controversial and complicated as MCS. See Scott Deitchman,Occupational and Environmental Medicine, 271 J. AM. MED. ASS’N 1691, 1691 (1994). This lack of training only exacerbates the difficulties that MCS patients face when they seek medical help.

[269] See, e.g., Gray, supra note 13, at 879 (discussing newly-opened Toronto clinic); Bradley v. Brown, 852 F.Supp. 690, 698 (N.D.Ind. 1994) (mentioning the Environmental Health Care Center in Dallas, TX); RADETSKY, supra note 11, at 86 (discussing the Environmental Allergy Center in Buffalo, N.Y.).

[270] The American Academy of Environmental Medicine (AAEM), founded in 1965, hosts nearly six hundred members; nearly one-third of all practicing environmental physicians. See id. at 79.

[271] See HUBER, supra note 18, at 93.

[272] RADETSKY, supra note 11, at 4; HUBER, supra note 18, at 96.

[273] See Berger, supra note 159, at 73.

[274] See Martin Hahn & Herbert L. Bonkovsky, Multiple Chemical Sensitivity Syndrome and Porphyria: A Note of Caution and Concern, 157 ARCH. INTERN. MED. 281, 282 (1997).

[275] See Berger, supra note 159, at 73.

[276] See Gray, supra note 13, at 880. Dr. Frank Foley, a family physician who serves as the clinic director, indicates that excessive sensitivity to smells is the most common symptom. Id.


[278] See Hahn & Bonkovsky, supra note 274, at 282. The symptoms and systems affected, such as memory loss and brain damage with related emotional and functional disruption from exposure to chemicals is well known in other contexts. See N. Fledler et al., Evaluation of chemically sensitive patients, 34 J. OCCUP. MED. 529-38 (1992); L.A. Morrow et al., PET and neurobehavioral evidence of tetrabromoethane encephalopathy, 2 J. NEUROPSYCHIATRY CLIN. NEUROSCI. 431-35 (1990).

[279] See AAAI Position Statement, supra note 162, at 270:

There is no clear evidence that many of the symptoms noted above are related to allergy, sensitivity, toxicity, or any other type of reaction from foods, water, chemicals, pollutants, viruses, and bacteria in the context presented.

[280] See Hahn & Bonkovsky, supra note 274, at 282.

[281] See id. at 284 (concluding that “there is no satisfactory evidence that decreased activity of coproporphyrinogen oxidase (leading to coproporphyrinuria) is a cause for multiple chemical sensitivity”).

[282] See Wendi J. Berkowitz, Multiple Chemical Sensibility in the Courtroom: Is there Life After Daubert?, 63 DEF. COUNS. J. 483, 483 (1996).

[283] See REES & PURCELL, supra note 265, at 143-44; RADETSKY, supra note 11, at 6 (quoting one patient as saying, “As long as I work at home, avoid rush-hour driving, stay away from people wearing perfume in close spaces, avoid buildings where the indoor air problem is obvious when I enter it, then I am able to function well enough to do my job”).

[284] Under this method, the treating physician intradermally injects a strong dose of an allergen, which provokes a reaction, then administers a “neutralizing” dose of the allergen through progressing dilutions of strong to weak. See id. at 88. Other treatments also include nutritional therapy and “heat therapy,” which involves literally sweating the toxins out of one’s system. See id. at 83.

[285] See Multiple Chemical Sensitivity (MCS) – A Disorder Triggered by Exposures to Chemicals in the Environment (visited Feb. 17, 1999) <>.

[286] See Simon et al., supra note 265, at 99; Gray, supra note 13, at 880; RADETSKY, supra note 11, at 14-15.

[287] See Luster et al., supra note 266, at 389.

[288] See, e.g., Bradley v. Brown, 852 F.Supp. 690, 700 (N.D.Ind. 1994), aff’d, 42 F.3d 434 (7th Cir. 1994); Carlin v. FRE Indus., Inc., No. 88-CV-842, 1995 WL 760739, at *4 (N.D.N.Y. Nov. 27, 1995); Sheila Jasanoff, Science on the Witness Stand, 6 ISSUES IN SCI. & TECH. 80, 86 (1989) (identifying criticisms of the theory and methods of clinical ecology by the American Academy of Allergy and Immunology and the California Medical Association).

[289] Cf. KUHN, supra note 5, at 24 :

Mopping-up operations are what engage most scientists throughout their careers. They constitute what I am here calling normal science. Closely examined, whether historically or in the contemporary laboratory, that enterprise seems an attempt to force nature into the preformed and relatively inflexible box that the paradigm supplies. No part of the aim of normal science is to call forth new sorts of phenomena; indeed those that will not fit into the box are often not seen at all.

[290] See id. at 97.

[291] In this sense, the etiology of a disease is the assignment of a cause for the disease. See WEBSTER’S NEW WORLD DICTIONARY 481 (2nd College ed. 1970).

[292] Dr. William J. Rea, a clinical ecologist frequently called upon to testify regarding MCS causation, has observed that 13 percent of his patients related the onset of their MCS to a “severe acute exposure,” 12 percent who “associated massive trauma with the start of the illness,” 9 percent who “identified childbirth as the triggering event,” 2 percent who “traced the onset to surgery,” and 1 percent who linked the onset of their illness to other causes. The remaining patients developed MCS from cumulative long term exposures over time. See WILLIAM J. REA, 1 CHEMICAL SENSITIVITY 9-10 (1992).

[293] See Simon et al., supra note 265, at 97.

[294] See Gray, supra note 13, at 880.

[295] A “signature illness” is a disease known to be caused by one specific agent; for example, mesothelioma is caused specifically be exposure to asbestos. See In re Joint E. & S. Dist. Asbestos Litig., 827 F.Supp. 1014, 1026 (S.D.N.Y. 1993).

[296] See Carolyn Needleman, Applied epidemiology and environmental health: Emerging controversies, 25 AJIC 262, 265 (1997).

[297] See supra notes 276, 277 and accompanying text (discussing symptoms and categories of symptoms).

[298] See RADETSKY, supra note 11, at 15 (citing the multitude of symptoms as one of the primary reasons that the American Medical Association has rejected MCS as a “recognized clinical entity,” adding that it is “[a]n old saw in medical circles is that the more numerous the symptoms, the less credible the patient”).

[299] See In re Breast Implant Cases, 942 F.Supp. 958, 960 (E.&S.D.N.Y. 1996) (indicating that “there are hundreds of symptoms associated with the differentiated” silicone-induced autoimmune disease).

[300] See Robert W. Haley et al., Is There a Gulf War Syndrome? Searching for Syndromes by Factor Analysis of Symptoms, 277 J. AMERICAN MED. ASS’N 215, 218-19 (1997) (listing approximately fifty distinct reported symptoms associated with the illness and identifying the characteristics of each of the six syndromes); Technology Assessment Workshop Panel, The Persian Gulf Experience and Health, 272 J. American Med. Ass’n 391, 391 (1994) (listing several symptoms that “may not fit readily into a common diagnosis”).

[301] Excessive sensitivity to smell, common among MCS patients, is a symptom that “traditional medicine cannot explain,” states one MCS clinic doctor. See Gray, supra note 13, at 880 (quoting Dr. Frank Foley, director of the Toronto Environmental Health Clinic).

[302] See HUBER, supra note 18, at 94 (observing that “[t]oday’s clinical ecologists are a varied group, a mix of general practitioners, psychiatrists, urologists, and pediatricians’); Luster et al., supra note 266, at 390 (observing that many clinical ecologists were “formerly traditional allergists or laryngologists”).

[303] See WEBSTER’S NEW WORLD DICTIONARY 267 (2nd College ed. 1970); see also HUBER, supra note 18, at 94 (indicating that few clinical ecologists have scientific training in laboratory or clinical research).

[304] See id. at 442.

[305] Cf. The Endangered Species Act, 16 U.S.C. § 1531(b) (1996) (discussing the role of ecosystems in endangered species protection); Oliver A. Houck, On the Law of Biodiversity and Ecosystem Management, 81 MINN. L. REV. 869, 877-79 (1997) (distinguishing single-species approaches from ecosystem approaches to listed species management).

[306] Summers v. Mo. Pacific R.R. System, 132 F.3d 599 (10th Cir. 1997).

[307] See id. at 603 (saying that if plaintiff is actually claiming to suffer from MCS, then the “defendant prevails because MCS is a controversial diagnosis that has been excluded under Daubert as unsupported by sound scientific reasoning or methodology”) (citing Bradley v. Brown, 42 F.3d 434, 438-39 (7th Cir. 1994); FOSTER & HUBER, supranote 35, at 59). This author finds it interesting that the Tenth Circuit would cite the Foster & Huber book, given the obvious bias that the authors hold against any novel scientific theory; particularly the use of such theory in the courtroom.

[308] See Zwillinger v. Garfield Slope Housing Corp., No. CV 94-4009 (SMG), 1998 WL 623589 (E.D.N.Y. Aug. 17, 1998).

[309] See Summers, 132 F.3d at 603; Coffin v. Orkin Exterminating Co., 20 F.Supp.2d 107, 110 (D.Me. 1998).

[310] FOSTER & HUBER, supra note 35, at 53.

[311] Berger, supra note 159, at 73-74. This specific passage is cited in several MCS causation cases. See Coffey v. County of Hennepin, 23 F.Supp.2d 1081, 1086 (D.Minn. 1998); Coffin, 20 F.Supp.2d at 110-11; Summers v. Mo. Pacific R.R. System, 897 F.Supp. 533, 535 (E.D.Okla. 1995).

[312] See Berger, supra note 159, at 74 (observing that “recent studies may provide some support for their claims” and that “numerous other professional organizations and societies . . . have not discredited completely the potential usefulness of clinical ecology”).

[313] See Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 1001 (C.D.Cal. 1996);

[314] See id. at 1001-02 (repeating defendant’s argument that expert opinion as to MCS should be excluded for the particular reason that various medical organizations do not believe that the illness exists and that any testimony about MCS would be unreliable for that reason). The court then added that its research “has revealed that every court to rule on this issue has agreed with defendant’s argument.” Id. at 1001. The court later added that it had “discovered no case in which MCS was recognized as a legitimate medical condition.” Id. at 1002. This assertion is in direct contradiction, however, to cases that have recognized its existence for the purposes of the Fair Housing Act. See infra note 395 (citing law review article on the subject). In another case, the court cited “serious doubts as to the scientific validity of the multiple chemical sensitivities syndrome,” and would as such exclude the plaintiff’s expert testimony even if it were scientifically valid. Carlin, 1995 WL 760739, at *4.

[315] Treadwell v. Dow-United Technologies, 970 F.Supp. 974, 981-82 (M.D.Ala. 1997). After citing the Federal Judicial Center’s Reference Manual and statements by various medical and scientific organizations about the perceived illegitimacy of MCS and clinical ecology, the court in Treadwell merely adopted the “reasoning and conclusions of theBradley and Summer courts,” concluding that MCS etiology and the practice of clinical ecology were scientifically unreliable. Id. at 982.

[316] 852 F.Supp. 690 (N.D.Ind. 1994. See Carlin, 1995 WL 760739, at *5 (relying upon the disposition of the Bradleycourt because it examined “literally hundreds of pages of material discussing MCS” and “considered these materials in depth”); Summers v. Missouri Pac. R.R. Sys., 897 F.Supp. 533, 542 (E.D.Okla. 1995), aff’d, 132 F.3d 599 (10th Cir. 1997) (adopting the reasoning and conclusions of Bradley and holding that plaintiffs “failed to show that the theories concerning MCS’s causes have been adequately tested”); Sanderson v. Int’l Flavors and Fragrances, Inc., 950 F.Supp. 981, 1002 (C.D.Cal. 1996) (concluding that, “given the present knowledge, Bradley and Summers correctly determined that MCS does not represent the reliable ‘scientific knowledge’ which Daubert and FED. R. EVID. 702 require”).

[317] Bradley, 852 F.Supp. at 700. This language has been cited by several cases as precedent for the “unreliable” nature of the science of MCS. See Coffin v. Orkin Exterminating Co., 20 F.Supp.2d 107, (D.Me. 1998); Treadwell v. Dow-United Technologies, 970 F.Supp. 974, 982 (M.D.Ala. 1997); Frank v. State of New York, 972 F.Supp. 130, 136 (N.D.N.Y. 1997); Sanderson, 950 F.Supp. at 996; Summers, 897 F.Supp. at 538; Carlin, 1995 WL 760739, at *5.

[318] See Bradley, 852 F.Supp. at 698 (citing the testifying expert’s book on MCS as indicating that thirteen percent of his patients “relate the onset of their sensitivity to a sever acute [chemical] exposure” and some nine percent who “identified childbirth as the triggering event”).

[319] See id. at 699-700.

[320] See id.

[321] See id. at 699 (once again citing expert’s book as saying, “[W]e do not know at this time the initial mechanism by which good health gives way to chemical sensitivity”).

[322] No. CV 94-4009 (SMG), 1998 WL 623589 (E.D.N.Y. Aug. 17, 1998).

[323] Zwillinger, 1998 WL 623589, at *10-*16. Despite the court acknowledging the controversial nature of MCS and how it has not been accepted by any federal court, see id. at *11, it still conducted this in depth review.

[324] See id. at *12 (citing a study that stated, “With regard to the issue of multiple chemical sensitivity (MCS), . . . evidence of an association with 4-PC is lacking”). The plaintiff also submitted forty-five other scientific studies “comprising several hundred pages,” but failed to cite the specific pages within those studies that supported her position. Id. The court noted that the responsibility to locate the specific pages was the plaintiff’s burden, not the courts, for “[d]istrict judges are not archaeologists. They need not excavate masses of papers in search of revealing tidbits.” Id. (quoting Northwestern Nat’l Insurance co. v. Baltes, 15 F.3d 660, 662 (7th Cir. 1994)). The court did, however, conduct a cursory review of the cited animal studies and concluded that they provided no valid basis for being extrapolated to humans. See id. at *13. One particular study heated a carpet sample in an aquarium to a temperature slightly above room temperature, then exposed the mice, in an adjacent chamber, to the heated air containing emissions from the carpet. The court failed to see how the reactions of mice to heated carpeting could be analogized to humans being exposed to carpet at room temperature. See id.

[325] See id. at *15. The plaintiff’s expert was conducting a study, which he planned to have published in the Archives of Environmental Health, that consisted of a case-control study of eighty-nine of his current MCS patients with symptoms and triggers similar to the plaintiff’s.

[326] See id. at *17. But see Kannankeril v. Terminix Int’l, Inc., 128 F.3d 802, 809 (3rd Cir. 1997) (observing that the since the effects of organophosphates on humans was well documented, it was not necessary that the plaintiff’s witness himself had published any articles on the theory).

[327] See Zwillinger, 1998 WL 623589, at *18 (citing the lack of an objective test for determining the cause of elevated antibody levels in the patients’ blood, the reliance on self-reported patient histories, and the lack of a control group).

[328] See id. at *21-23. The court concluded that, although the plaintiff’s expert tried to avoid the MCS controversy and lack of general acceptance by calling it “immunotoxicity” or “toxic encephalopathy,” the hypothesis that exposure to gases given off by carpeting may cause MCS is not generally accepted in the scientific community.

[329] See id. at *19-20.

[330] See, e.g., In re Breast Implant Cases, 942 F.Supp. 958, 960 (E.&S.D.N.Y. 1996):

The hundreds of symptoms associated with this undifferentiated disease, the lack of any acceptable agreed upon definition, the inadequacy of any satisfactory supporting epidemiological or animal studies, the lack of a scientifically acceptable showing of medical plausibility, and the questionable nature of the clinical conclusions of the treating doctors, all point to a failure of proof in making a prima facie case that silicone implants cause any of the syndromes claimed except for local disease.

Having taken the time to say all of that, the district court still denied summary judgment for the defendants. The court deferred pending the outcome of a national study: “It is possible that further information will in time support the plaintiffs’ general systemic claims sufficiently to permit a jury trial.” Id. at 961.

[331] This is a limited scope of inquiry. Due to the complex nature of MCS, the diversity of persons claiming to suffer from MCS, the multiplicity of suspected triggers, and the vast number of displayed symptoms, it would be impractical and implausible to conduct a discussion on how to prove either general or specific causation. The purpose of this discussion is to isolate the weaknesses in judicial analysis of the “scientific knowledge” associated with MCS and to indicate how judges should be able to admit causation testimony with a proper application of the spirit and the letter of Daubert.

[332] Nor will this author attempt to do so.

[333] See Underwagner v. Salter, 22 F.3d 730, 736 (7th Cir. 1994) (“Scientific controversies must be settled by the methods of science rather than by the methods of litigation”).

[334] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 597 (1993) (discussing the need for quick, final, and binding decisions in the law); Peter H. Schuck, Multi-Culturalism Redux: Science, Law, and Politics, 11 YALE L. & POL’Y REV. 1, 25 (1993):

The law is usually in much more of a hurry to decide than science is. Ironically, however, law’s findings, although less reliable and tested than those of science, are treated as more final and authoritative. Law operates under pressure to resolve particular disputes speedily and conclusively . . . [Scientific] consensus often takes a long time to assemble, yet even then it is conditional, always open to revision on the basis of new data or theories.

[335] Most courts that hold a methodology to be unreliable also conclude that the proffered testimony fails to “fit” the facts of the case, or be deemed relevant. See, e.g., Zwillinger v. Garfield Slope Housing Corp., No. CV 94-4009 (SMG), 1998 WL 623589 (E.D.N.Y. Aug. 17, 1998). Courts that view a scientific theory to be not generally accepted will also likely hold that the science has not been subjected to peer review. See, e.g., id. The remaining two components, subject to empirical testing and error rate, are more case specific and harder to illustrate for purposes of this exercise.

[336] See Daubert, 509 U.S. at 589 (rejecting the “generally accepted” standard as “austere” and “absent from and incompatible with the Federal Rules of Evidence”).

[337] See United States v. Williams, 447 F.2d 1285, 1290 (5th Cir. 1971), cert. denied, 405 U.S. 954 (1972), reh’g denied, 405 U.S. 1048 (1972) (arguing that Rule 703 is designed to perform this function).

[338] Any discussion of peer review or general acceptance is notably absent from Karl Popper’s validity assessment,see supra note 47, Carl Sagan’s “baloney detection kit,” see infra note 365, and the “Koch-Henle Postulates,” see infranote 366. It would seem that the scientific community is only deeply concerned about peer review and general acceptance when litigation is involved.

[339] See supra notes 309-315 and accompanying text (recounting the weight of this factor alone in having MCS causation testimony excluded).

[340] See Treadwell v. Dow-United Technologies, 970 F.Supp. 974, 981 (M.D.Ala. 1997) (quoting a statement on MCS by the American College of Occupational and Environmental Medicine as finding that “[t]he scientific foundation for managing patients with this syndrome has yet to be established by traditional investigative activities that withstand critical peer review”).

[341] See supra note 284 for a description of the provocation-neutralization method.

[342] Single Photon Emission Tomography. Similar to CAT and PET scans, SPECT tracks the flow of blood into the brain and the brain’s ability to utilize that blood. Clinical ecologists and other practitioners who treat MCS use this technique to measure neurophysical reactions to toxic exposures. See RADETSKY, supra note 11, at 107.

[343] See id. at 87.

[344] Doris Rapp conducted a double-blind study on the provocation neutralization method, but was rejected by the traditional medical journals in the United States. She eventually published in the Medical Journal of Australia. Claudia Miller has suggested that the standards expected by mainstream scientific and medical journals is higher for MCS than other subjects: “The standards for MCS papers are much more exacting, scrutiny is much more intense, because many scientists don’t believe it exists.” Id. at 142-44.

[345] William J. Rea was previously a cardiovascular surgeon who started making connections between blood clotting and artificial lungs and hearts. After conducting extensive research and study on the matter, he wrote a paper and submitted it to the Journal of the American Medical Association. He recalls their response: “This is a novel concept. Nobody on the reviewing panel has ever heard of such a thing. Therefore, we’re gonna reject it.” Id. at 82. Since then, the mere mention of Bill Rea’s name in an article will guarantee rejection. See id. at 142 (recounting the experience of an academic physician, not a clinical ecologist, who tried to publish an article in one of the leading medical journals but was told by the editorial staff, “If you expect to publish in this journal you will not cite any work by Bill Rea”) (emphasis original).

[346] Daubert v. Merrell Dow Pharmaceuticals, Inc., 43 F.3d 1311, 1319 (9th Cir. 1995) (adding that a methodology must constitute “the scientific method, as it is practiced by (at least) a recognized minority of scientists in their field” (emphasis added)).

[347] See id.; United States v. Downing, 753 F2d 1224, 1238 (3rd Cir. 1985).

[348] See, e.g., Viterbo v. Dow Chemical Co., 826 F.2d 420, 421 (5th Cir. 1987) (stating that the plaintiff’s expert “brought to court little more than his credentials and a subjective opinion”); Buckley & Haake, supra note 76, at 10293 (suggesting that the “so-called experts” are “well paid” for their “unsupported opinions”).

[349] Of course, it is easy to ridicule that theory if you work for the industries contributing to the toxicity of the environment. See supra notes 9, 265 (discussing influence of industry upon “objective” scientific study). A useful analogy to articulating a sensible theory might be found in death by exsanguination. It takes no stretch of imagination to believe that a deep cut across the carotid artery would cause quick and certain blood loss, and eventually death, absent adequate medical attention. It is harder to accept a theory that death was caused by a scratch, unless that scratch was one of a thousand over a short period of time, and the victim was a hemophiliac. This scratch analogy most aptly fits the primary theories over what causes MCS.

[350] See, e.g., The X-Files: Momento Mori (Fox Television broadcast, Feb. 9, 1997). In this episode, FBI Special Agent Dana Scully is diagnosed with cancer and learns about the origins of her illness by contacting a group of purported female abductees who experienced similar symptoms after having implants removed from the base of their necks.

[351] See BEAGLEHOLE ET AL., supra note 62, at 117. For example, 80 percent of all cancer is caused by environmental factors. See id.

[352] See id. at 118, Fig. 9.1.

[353] See id. at 125.

[354] See Luster et al., supra note 266, at 379-81 (discussing scientific studies and adding that “these immune system problems are well established and accepted by the medical community”).

[355] See, e.g., Needleman, supra note 296, at 266 (discussing the increased vulnerability of children to pesticides in food products).

[356] These three “lines of evidence” include: The use of powerful drugs for cancer treatment or to suppress the immune system of patients following organ transplants, several occupational or inadvertent exposures to chemicals that have resulted in immunologic changes, and “scattered studies” that report both immune suppression and “clinically apparent health defects” in people following occupational or accidental exposure to chemicals. See Luster et al., supra note 266, at 383 (discussing studies and providing details).

[357] See id. at 385. In addition, the National Academy of Sciences has suggested that fifteen percent of all Americans may experience “increased allergic sensitivity” to chemicals. And a 1991 survey by the U.S. Environmental Protection Agency found that approximately one-third of inhabitants of sealed buildings reported sensitivity to one or more common chemicals. See RADETSKY, supra note 11, at 12.

[358] Despite knowledge about substances that are likely to cause cancer, scientists still have much to learn about cancer’s etiology. See, e.g., Suzanne V. Cocca, Who’s Monitoring the Quality of Mammograms? The Mammography Quality Standards Act of 1992 Could Finally Provide the Answer, 19 AM. J.L. & MED. 313, 313 (1993) (asserting that little is known about the etiology and prevention of breast cancer); Charles Nesson, Agent Orange Meets the Blue Bus: Factfinding at the Frontier of Knowledge, 66 B.U. L. Rev. 521, 526 (1986) (stating that “the etiology of cancer is not yet known; scientists cannot explain at a cellular level the mechanism of causation”).

[359] Rita Linggood et al., A Blueprint for Linking Academic Oncology and the Community, 23 J. HEALTH POL. POL’Y & L. 973, 982 (1998) (listing some treatments as “combined modality therapy with chemotherapy plus radiation, radiation sensitizers, hyperthermia, brachy-therapy, physical dose-localization approaches” and others).

[360] Several anatomical systems are affected by cancer, from neurological to cardiovascular; even immunological. See, e.g., National Cancer Institute, Cancer Information Summaries (visited March 28, 1998) <>.

[361] Cancer symptoms will reflect the organ or system being attacked. See id.

[362] See generally William Brietbart et al., Neuropsychiatric Syndromes and Psychological Symptoms in Patients with Advanced Cancer, 10 J. PAIN SYMPTOM MGMT. 131 (1995).

[363] See United States v. Downing, 753 F.2d 1224, 1240 (3rd Cir. 1985).

[364] This has been suggested by one author to be a “fidelity” requirement. See Kesan, supra note 172, at 2021.

[365] Carl Sagan, well-known for his popularization of the field of astronomy, combined some of the traditional elements of proper methodology with a few of his own to build a criteria for establishing sound theory he referred to as a “baloney-detection kit”:

What’s in the kit? Tools for skeptical thinking.
What skeptical thinking boils down to is the means to construct, and to understand, a reasoned argument and – especially important – to recognize a fallacious or fraudulent argument. The question is not whether we like the conclusion that emerges out of a train of reasoning, but whether the conclusion follows from the premise or starting point and whether that premise is true.

Among the tools:
 Wherever possible there must be independent confirmation of the “facts.”
 Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
 Arguments from authority carry little weight – “authorities” have made mistakes in the past. They will do so again in the future . . .
 Spin more than one hypothesis . . . What survives, the hypothesis resists disproof in this Darwinian selection among “multiple working hypotheses,” has a much better chance of being the right answer than if you simply run with the first idea that caught your fancy.
 Try not to get overly attached to a hypothesis just because it’s yours . . .
 Quantify. If whatever it is you’re explaining has some measure, some numerical quantity attached to it, you’ll be much better able to discriminate among competing hypotheses. What is vague and qualitative is open to many explanations . . .
 If there’s a chain of argument, every link in the chain must work (including the premise) – not just most of them.
 Occam’s Razor. This convenient rule-of-thumb urges us when faced with two hypotheses that explain the data equally well to choose the simpler.
 Always ask whether the hypothesis can be, at least in principle, falsified. Propositions that are untestable, unfalsifiable are not worth much . . .


[366] See, e.g., Bruce A. Parker, Effective Strategies for Closing the Door on Junk Science Experts, 65 DEF. COUNS. J. 338, 343 (1998) (suggesting a strict adherence to the Bradford-Hill criteria as a means for challenging scientific data). The Bradford-Hill criteria are as follows:

(1) Strength of association (epidemiological evidence);
(2) Consistency of association (are the epidemiological studies consistent?);
(3) Specificity of association (are one or more diseases implicated with exposure to agent?);
(4) Biological gradient (does the exposure produce a dose-response?);
(5) Biologic plausibility;
(6) Coherence (are the data consistent?);
(7) Experiment (does the effect disappear in experimental animals when the suspected agent is removed?); and
(8) Analogies (do analogies suggest causal inferences?).

Id. (citing no authority for the criteria, but stating that it was “originally proposed in 1965 in an interpretive framework for analyzing whether an association existed between cigarette smoking and lung cancer’). See also Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp.2d 942, 972 (E.D.Ark. 1998) (discussing a similar process previously known as “Koch’s Posutlates” then later as “Koch-Henle Postulates”); PHANTOM RISKS, supra note 76, at 7 (discussing the “Henle-Koch-Evans (HKE) Postulates”); Alfred S. Evans, Causation and Disease: The Henle-Koch Postulates Revisited, 175 YALE J. OF BIO. & MED. 49 (1976) (identifying the ten principles of the Henle-Koch Postulates).

[367] See Needleman, supra note 296, at 265.

[368] See Bailey et al., supra note 65, at 133 (stating that observational studies “allow the researcher to draw stronger inferences about associations between risk factors and disease”).

[369] See, e.g., Treadwell v. Dow-United Technologies, 970 F.Supp. 974, 982 (M.D. Ala. 1997) (noting that the parties had “failed to make it clear” that the provocation-neutralization method is scientifically valid and supported by sound methodology).

[370] See, e.g., Don L. Jewitt et al., A Double Blind Study of Symptom Provocation to Determine Food Sensitivity, 323 N. ENG. J. MED. 429 (1990) (concluding that the provocation-neutralization method “appears to lack scientific validity”); ASHFORD & MILLER, supra note 277, at 133 (arguing that even if they were ability to validate the provocation-neutralization method, “extension of this technique from inhalants and foods to chemicals such as formaldehyde, automobile exhaust, phenol, and tobacco smoke is a major leap of faith that needs much further investigation”).

[371] See Goldstein & Henifin, supra note 80, at 197 (noting that with toxic torts “[a] proposed expert should be able to demonstrate an understanding of the discipline of toxicology, including statistics, toxicological research methods, and disease processes”).

[372] See, e.g., Treadwell v. Dow-United Technologies, 970 F.Supp. 974 (M.D.Ala. 1997) (admitting testimony by expert who utilized allergy testing to prove plaintiff’s reactions to formaldehyde contributed to her illness).

[373] One MCS plaintiff’s expert was allowed to testify as plaintiff’s treating physician but was not allowed to testify to the methods of clinical ecology. See Treadwell, 970 F.Supp. at 984. The expert based his findings on “physical examination of the patient; the positive results of patch tests administered by [expert]; the patient history as provided by plaintiff herself; and the results of the first skin irritation test.” (emphasis added) Id. at 982.

[374] Hall v. Baxter Healthcare Corp., 947 F.Supp. 1387, 1413 (D.Or. 1996).

[375] See Pick v. American Medical Systems, Inc., 958 F.Supp. 1151, 1163 (E.D.La. 1997)

[376] See, e.g., Nat’l Bank of Commerce v. Assoc. Milk Producers, Inc., 22 F.Supp. 942, 963 (E.D.Ark. 1998) (admonishing plaintiff’s witness for not being diligent in “ruling in” a chemical that plaintiff was exposed to as a potential cause); Cavallo v. Star Enterprises, 892 F.Supp. 756, 770-71 (E.D.Va. 1995):

The process of differential diagnosis is undoubtedly important to the question of “specific causation.” If other possible causes of an injury cannot be ruled out, or at least the probability of their contribution to causation minimized, then the “more likely than not” threshold for proving causation may not be met. But, it is also more important to recognize that a fundamental assumption underlying this method is that the final suspected “cause” remaining after this process of elimination must actually be capable of causing injury.

[377] See In re Paoli Railroad Yard PCB Litig., 35 F.3d 717, 758 (3d Cir. 1994), cert. denied, 513 U.S. 1190 (1995); Pick, 958 F.Supp. at 1163; Wilson v. Petroleum Wholesale, Inc., 904 F.Supp. 1188, 1190 (D.Colo. 1995). See also Joiner v. General Electric Co., 78 F.3d 524, 530-33 (11th Cir. 1996); Benedi v. McNeil-P.P.C., Inc., 66 F.3d 1378, 1384 (4th Cir. 1995); McCullock v. H.B. Fuller Co., 61 F.3d 1038, 1043-44 (2d Cir. 1995).

[378] See Zuchowicz v. United States, 140 F.3d 381 (2nd Cir. 1998); Benedi, 66 F.3d 1378; In re Paoli, 35 F.3d 717.

[379] See In re Paoli R.R. Yard Litig., 35 F.3d 717, 758-59 (3d Cir. 1994):

[A]lthough differential diagnosis is a generally accepted technique, no particular combination of techniques chosen by a doctor to assess an individual patient is likely to have been generally accepted. But unlike a methodology used in conducting a scientific study, lack of general acceptance is not a sign of unreliability, it is merely a result of the fact that the medical community will rarely have considered the reliability of a particular process of differential diagnosis used in an individual case. Nor is it likely that the particular combination will have been published and subject to peer review, because a particular version of differential diagnosis will rarely be of general interest to the medical community. However, to the extent that a doctor utilizes standard diagnostic techniques in gathering this information, the more likely we are to find that the doctor’s methodology is reliable.

[380] See ASHFORD & MILLER, supra note 277, at 30 (characterizing the diagnostic and therapeutic modalities used by Alfred Johnson and William Rea as a “comprehensive environmental control with the use of an environmental unit” as “the gold standard”).

[381] See RADETSKY, supra note 11, at 84.

[382] See id. at 85.

[383] See Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 593 (1993) (noting that scientific explanations should be capable of empirical testing).

[384] Even Alfred Johnson and William J. Rea, the two experts most utilized in MCS cases and most despised by the scientific community, have been considered qualified to appear as experts. See, e.g., Bradley v. Brown, 852 F.Supp. 690, 697 (N.D.Ind. 1994) (noting that the defendant did not even question the qualifications of Drs. Johnson and Rea). For suggestions on a line of questions to ask expert in order to qualify, see Merilyn Brown, Establishing a Prima Facie Case Involving Multiple Chemical Sensitivity: A Threshold Approach, 29 J. MARSHALL L. REV. 441, 449-453 (1996).

[385] For example, there are specific questions a judge might ask a toxicology expert, such as: Does the expert have an advanced degree in toxicology, pharmacology, or a related field? Has the proposed expert been certified by the American Board of Toxicology, or does he or she belong to a professional organization? See Goldstein & Henifin,supra note 80, at 198.

[386] See Daubert, 509 U.S. at 596.

[387] See id. at 596-97.

[388] Brief research into this paper showed the author that not only have plaintiffs completely failed to introduce MCS causation evidence into the courtroom, but the scientific and medical community also denies its very existence. Even watching good television can be a source for such information. See supra note 266 (citing example from television show “Northern Exposure” as illustration of how the media recognizes the perceived illegitimacy of MCS).

[389] See generally James Podgers, Science Wizards, ABA JOURNAL, Feb. 1999, at 34 (featuring several attorneys who, in addition to the law, specialize in fields ranging from intellectual property to engineering). Susan R. Poulter, a professor at the University of Utah College of Law in Salt Lake City, suggests that attorneys attend ABA-sponsored courses on environmental science for lawyers and reading up on articles in scientific and technical journals. She adds that such self-education may be a good start to understanding science, but should never replace a good expert. Id. at 38. And in so understanding the methodologies of science, perhaps lawyers will do a better job of communicating scientific concepts of causation as well. See Snyder et al., supra note 111, at 131 (remarking on the changing nature in scientific causation, that is, being modified to allow for probability, while being poorly articulated in legal discussions on causation).

[390] See Foster et al., supra note 93, at 1509 (opining that “[m]uch of the scientific evidence that has been presented in toxic tort suits has questionable relevance to public health,” mentioning high-dose animal studies as an example).

[391] See David L. Faigman, Mapping the Labyrinth of Scientific Evidence, 46 HASTINGS L. J. 555, 556 (1995) (suggesting that judges should become “sophisticated consumers of science”).

[392] In his concurring opinion, Chief Justice Rehnquist stated that he did not think the gatekeeping function imposed on judges either the obligation or authority “to become amateur scientists in order to perform that role.” Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 600-01 (1993) (Rehnquist, C.J. concurring).

[393] See Needleman, supra note 296, at 266 (“It may be many years before scientific understanding catches up with the possibilities suggested by recent research” into environmentally related illnesses). But see Moore v. Ashland Chemical Co., 151 F.3d 269, 276 (5th Cir. 1998) (“[T]he law cannot wait for future scientific investigation and research. We must resolve cases in our courts on the basis of scientific knowledge that is currently available”). For a criticism of the Moore decision, see generally Thomas M. Reavley & Daniel A. Petalas, A Plea for Return to Evidence Rule 702, 77 TEX. L. REV. 493, 493 (1998) (beginning their argument by saying that the Moore decision “is such an abuse of Rule 702 and a distortion of the Supreme Court’s opinion in Daubert“).

[394] 42 U.S.C. § 3604(f)(2) (1996) (declaring it unlawful to discriminate against any person in a dwelling because of a handicap).

[395] See generally Brown, supra note 384, at 444-49 (discussing elements of a FHA claim and relevant case law).

[396] In fact, employers establish procedures and guidelines for addressing the illness. See, e.g.Internal Guidelines regarding Multiple Chemical Sensitivity/Environmental Illness (MCS/EI) for Disability Services at the University of Minnesota, <> (last visited Feb. 17, 1999). But see Eric Nelson & Mark Worth, Boeing to Ill Workers: “It’s All In Your Head”, WASH. FREE PRESS, Feb./Mar. 1994 (discussing a pattern of harassment directed against employees who claimed to have MCS).

[397] Americans With Disabilities Act of 1990, Pub.L. 101-336, July 26, 1990, 104 Stat. 327.

[398] See generally Frank v. State of New York, 972 F.Supp. 130 (N.D.N.Y. 1997); Andrew K. Kelley, Comment,Sensitivity Training: Multiple Chemical Sensitivity and the ADA, 25 B.C. ENVT’L AFF. L.REV. 485 (1998).

[399] See, e.g., Dick Thornburgh, Junk Science: The Lawyer’s Ethical Responsibilities, 25 FORDHAM URB. L.J. 449, 449 (1998):

Broadly speaking, I hold that “junk science” in the courtroom emanates from testimony by expert witnesses hired not for their scientific expertise, but for their willingness, for a price, to say whatever is needed to make the client’s case. Put simply, I believe that it is unethical lawyers who are largely to blame for introducing, or, in settlement negotiations, threatening to introduce this so-called “expert” testimony.

[400] Judges must also be mindful, as cited numerous times in this article, that science is inherently subjective, easily manipulated, and hostile to dramatically new theories, regardless of their scientific validity. New theories, or paradigms, will always require widespread reevaluation of science, particularly when the old rules no longer fit new developments.

[401] See generally Berkowitz, supra note 282 (displaying not only disdain for the “fad disease” of the twentieth century, but an obvious lack of compassion for the so-called “victims” of MCS); cf. generally Parker, supra note 366 (offering suggestions on how to protect the courtroom against illegitimate science).

[402] One of the “dark times” for credibility of the legal use of scientific expert testimony was the period in American Tort Jurisprudence when courts readily admitted plaintiffs’ scientific evidence that “proved” a blunt-trauma injury later caused cancer in the same location. See, e.g., White v. Valley Land Co., 322 P. 707 (N.M. 1958) (holding that plaintiff’s bone cancer was caused by injury to leg suffered while doing some heavy lifting); Emma v. A. D. Julliard & Co., 63 A.2d 786 (R.I. 1949) (deciding that a woman’s breast cancer was caused by a large can of orange juice hitting her in the chest); Traders & General Ins. Co. v. Turner, 149 S.W.2d 593 (Tex. Ct. App. 1941) (concluding that two severe blows to a man’s testicles caused his cancer); Winchester Milling Corp. v. Sencindiver, 138 S.E. 479 (Va. 1927) (finding that plaintiff’s cancer of the rib was caused by a five-foot fall from an elevator); Baetz v. City of Melrose, 193 N.W. 691 (Minn. 1923) (determining that police officer’s abdominal cancer was caused by an assault on his person); Canon Reliance Coal Co. v. Industrial Comm’n, 211 P. 868 (Colo. 1922) (finding that miner’s cancer was caused by blow to the face by a piece of coal ).

[403] See Robertson v. Norton Co., 148 F.3d 905, 907-08 (8th Cir. 1998) (holding that district court abused its discretion for allowing a ceramics expert to testify that warnings on a grinding wheel were inadequate).