Science, law, and truth: defining the scope of the Daubert trilogy.

• Author: Dillhoff, Megan

INTRODUCTION

The characteristic goals and the inherent exuberance of science generate a natural tendency toward progress and expansion. (1) That tendency finds particular expression in today's courtroom, where science offers insight into a wider array of legal disputes than at any time in the past. Experts testify "on blood, bullets, bite-marks, battered wives; on PCBs, paternity, poisons, post-traumatic stress; on radon, recovered memories, rape trauma syndrome, random-match probabilities; on psychosis, asbestosis, silicosis" (2)--and the list goes on. Scientific experts may comment on both civil and criminal matters, they may offer empirical or theoretical explanations, and they may speak from established or inchoate fields of inquiry. An unprecedented quantity of scientific evidence is available for use in American courtrooms and the complexity of available scientific information easily exceeds the expertise that may be expected of any single individual. As a result, the assessment of scientific evidence in the courtroom has become, not surprisingly, a controversial subject in American law.

The Daubert trilogy (3) attempts to give judges a methodology for evaluating scientific claims in the legal context. The trilogy is a series of three cases decided by the Supreme Court in the 1990s, each case dealing with some aspect of admissibility determinations for scientific evidence. (4) The Daubert trilogy presents guidelines for judges to apply when determining whether scientific evidence is admissible in federal court according to the parameters set by Rule 702 of the Federal Rules of Evidence. Importantly, these cases assign the role of gatekeeper primarily to judges rather than juries when it comes to scientific evidence and testimony. (5)

The Daubert decisions became the subject of intense intellectual discourse from the moment they were handed down. Since that time, scholars have written extensively on the application of the Daubert holdings to various types of scientific and technological evidence, including historian testimony, (6) behavioral science, (7) forensic evidence, (8) proof of injury in toxic tort litigation, (9) and valuations by experts in bankruptcy proceedings. (10) Some professors have directly criticized the Daubert decisions themselves. (11) Others have analyzed the integration of the trilogy with hallmarks of American justice--for example, the jury trial (12) and the adversarial process. (13) Still other scholars have offered predictions for the future of the judiciary after Daubert and have advocated an expansion of independent judicial research. (14)

An additional dimension of the Daubert holdings, however, has emerged in the past five years as the Daubert guidelines have become influential outside of the admissibility context in which they were developed. Judges facing cases with scientific import have used Daubert and its progeny to establish a jurisprudential foundation for resolving science and law questions even when the admissibility context has not been specifically at issue. This expansion of the Daubert guidelines outside of their initial domain presents significant questions about the reach and relevance of the Daubert standards. Scholars have yet to debate this aspect of the Daubert holdings fully.

This Note will analyze the Daubert holdings and their recent applications in contexts outside of pure admissibility decisions. Part I will outline the Daubert trilogy holdings. Part II will consider the philosophical distinctions between science and law and will illustrate how these fields resist integration and must be balanced against one another in holdings like those of the Daubert trilogy. Parts III and IV will examine two fields into which the use of the Daubert holdings has expanded beyond the traditional admissibility questions that the cases themselves decided: first, the Federal Vaccine Court's recent holdings concerning a possible scientific link between autism and childhood vaccinations; (15) and second, the Kitzmiller decision (16) at the district court level, which held that creationism could not be science, based in part on criteria set forth in the Daubert holdings.

This Note will conclude by recommending to future courts that the Daubert criteria be applied only where judges must necessarily balance the weight of competing scientific claims in order to resolve a particularized legal question; the vaccine-autism cases, like Cedillo, provide an example of such a situation. Future courts should avoid using the Daubert criteria to make nonessential evaluations concerning the philosophy of science, which should appropriately be left to experts and individuals as a matter of public opinion and the democratic process. Unlike the court in Kitzmiller, judges should confine their role to determining distinct questions of law that are explicitly relevant to discrete legal matters.

1. UNDERSTANDING THE DAUBERT TRILOGY

   The Daubert trilogy provides the fundamental legal framework for considering the admissibility of scientific and other technical evidence in federal courts. Understanding the law both before and after Daubert is essential to beginning any discussion about the scope of the Daubert holdings and the ways in which the application of these holdings should be expanded or limited.

   1. The Law Before Daubert

      Before the holdings in the Daubert trilogy of cases, federal courts in the United States had considered the admissibility of scientific evidence under the "Frye standard," derived from a brief, citation-free opinion issued in 1923. (17) In Frye v. United States, (18) the U.S. Court of Appeals for the D.C. Circuit considered the admissibility of scientific testimony supporting the use of a "systolic blood pressure deception test," (19) known more commonly today as a lie detector test. At that time, the admission of systolic blood pressure tests had yet to be supported by any court. (20)

      The Frye case directly confronted the nebulous question of how courts should determine the accuracy and validity of scientific evidence and to what extent expert opinions should be guarded by judges and to what extent they should be available to juries. In settling this issue, the court articulated what would come to be known as the Frye standard, stating:

      Just when a scientific principle or discovery crosses the line between the experimental and demonstrable stages is difficult to define. Somewhere in this twilight zone the evidential force of the principle must be recognized, and while courts will go a long way in admitting expert testimony deduced from a well-recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs. (21) This standard of "general acceptance" required judges to look to the scientific community as a whole in order to assess the validity of scientific evidence. Evidence was deemed to be inappropriate for juries if it was not the subject of general acceptance among scientific professionals. (22)

      The Frye standard of general acceptance survived for over seventy years as the dominant, though not the only, standard for the admissibility of scientific evidence in federal courts. (23) The Frye standard was not without critique, however, and resistance to the standard grew over time, particularly because the test was difficult to apply and frequently generated anomalous results. (24) Though the Frye test appeared to require only a single, simple level of inquiry--that of determining "general acceptance"--in reality, the test required multiple steps of evaluation, each fraught with its own difficulties. (25) Courts needed to determine the proper scientific field in which to look for general acceptance. (26) Courts also needed to decide exactly what part of the evidence required general acceptance; was it the explanatory scientific theory behind a particular technique or merely the technique itself? (27) And finally, courts had to choose which type of evidence to use to determine general acceptance--expert testimony, scientific literature, judicial opinions, or some combination thereof. (28)

      By the 1970s, attacks on the Frye test had emerged from both courts and commentators. (29) Some critics said the test was too conservative because it kept out reliable scientific information that was simply too new to be generally disseminated and accepted within the scientific community. (30) Such an exclusion amounted to a requirement for "cultural lag" in judicial decisions, forcing courts to operate at a distance from current scientific thought and to prefer older information simply because it had been discovered earlier. (31) The adoption of the Federal Rules of Evidence, which became effective in 1975, further challenged the Frye test by leading courts to question whether the new Rules required modifications to the general acceptance standard. (32) Rule 702 addressed the admission of expert testimony but did not employ the phrase "general acceptance," thereby prompting concerns over whether or not the Frye test had survived the passage of the Rules. (33) By 1980, the Frye test had splintered into several alternative interpretations applicable in different jurisdictions. (34) At that time, rejection of the Frye test became an open discussion and courts and commentators began exploring new ways to approach the admission of scientific evidence in the courtroom. (35)

   2. Daubert v. Merrell Dow Pharmaceuticals, Inc.

      In Daubert v. Merrell Dow Pharmaceuticals, Inc. (36) the Court resolved the tension between the Federal Rules of Evidence and the Frye test by finding that the Rules had superseded Frye, resulting in a more inclusive and permissive standard for the admission of scientific evidence in federal court. (37) The Daubert plaintiffs were a pair of minor children born with serious birth defects who alleged through their parents in...