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by J. Scott Janoe - Harvard Law School '99
Expert witnesses have become fixtures in today's courts. From fiber comparisons to economic projections to psychiatric evaluations, the range of offered expertise covers the span of human knowledge. Hardly a case of any consequence goes to trial without expert testimony of some kind. With such widespread use of expert testimony comes the inevitable question: "what is the trial judge's role in overseeing the testimony of expert witnesses?" Unlike lay witnesses, whose testimony a jury can evaluate based on common sense and experience, expert witnesses offer conclusions based on practices and knowledge beyond the ken of the average juror. As a consequence, testimony by unpoliced expert witnesses can have a potentially prejudicial effect on jurors, who may be inclined to believe the experts solely because of their "expert status." How is the trial judge to know whether the expert is merely speculating, or whether the evidence on which the expert bases his or her conclusions is sufficient to support the conclusion? Judges certainly prevent lay witnesses from speculating and are expected to exclude the testimony of a witness offering wholly speculative evidence. Why should this mandate be any different when the witness purports to be an expert?
If one accepts the proposition that the trial
judge has a duty to exclude unreliable experts, a host of concerns inevitably
follows. How is a trial judge to assess the scientific or technical adequacy
of expert testimony if even a cursory understanding of the issues requires
specialized training? Can anyone without such training fully understand
the issues and come to a rational conclusion as to their validity? To what
degree can the trial judge rely on the expert's own assertions about his
or her qualifications? All of these concerns carry heavy weight for in
many cases the trial judge is hardly a more qualified assessor of scientific
credibility than the jury itself. In this introduction and the papers which
follow it, we have laid out some possible answers to the myriad questions
raised by judicial gatekeeping. This first paper attempts to establish
a historical perspective on gatekeeping in Alaska. The papers that follow
it give a more generalized picture of the gatekeeping debate. Ultimately
we hope that you find these materials helpful in formulating or fine-tuning
your own approach to science in the courts.
From Frye to Daubert:
Judicial Gatekeeping in the Federal Courts
With the adoption of the Federal Rules of Evidence in 1975, courts, scholars and practitioners alike began to question whether Fryewould survive as the sole admissibility standard for expert testimony. Under the Federal Rules, judges were seemingly afforded more discretion in making admissibility determinations. Rule 104(a) assigns judges the responsibility of making a preliminary determination on whether to allow a given expert to testify. Rule 702 goes on to guide this decision by requiring the judge to determine whether the admission of such testimony will assist the trier of fact to understand evidence or determine a fact at issue. Finally, Rule 403 suggests that the judge may exclude evidence if its likely prejudicial effect outweighs its probative value. The question was then to what degree would the arguably conservative Frye general acceptance standard survive in the wake of the presumably more liberal admissibility framework embodied in the new Federal Rules of Evidence.
The U.S. Supreme Court endeavored to answer the question of Frye's continued viability in Daubert v. Merrell Dow Pharmaceuticals, Inc.(3) In Daubert the Court held that Rule 702 did in fact supersede the Frye standard and enumerated a new standard to instruct judges on how to act as judicial gatekeepers. This new approach consisted of a two-pronged analysis of the testimony centering on the testimony's reliability and relevance. In determining reliability the court must engage in a, "preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts at issue."(4) In addition, when determining scientific reliability the trial judge should consider:
(1) whether the proffered knowledge can be or has been tested, (2) whether the theory or technique has been subjected to peer review and publication, (3) the known or potential rate of error, and (4) whether the theory or technique has gained general acceptance in the relevant scientific discipline.(5)This nonexhaustive list of indicia of reliability relegated the Frye standard to one of a handful of guidelines that may be employed in ruling on admissibility. In conjunction with the newly ordained relevancy prong, the reliability criteria form a substantially more robust framework with which to analyze given scientific testimony.
Joiner: Abuse of Discretion
The Supreme Court reversed the Court of Appeals and noted that such a "particularly stringent" standard of review was improper in this context:
Thus, while the Federal Rules of Evidence allow district courts to admit a somewhat broader range of scientific testimony than would have been admissible under Frye, they leave in place the "gatekeeper" role of the trial judge in screening such evidence. A court of appeals applying "abuse of discretion" review to such rulings may not categorically distinguish between rulings allowing expert testimony and rulings which disallow it. We likewise reject respondent's argument that because the granting of summary judgment in this case was "outcome determinative," it should have been subject to a more searching standard of review. On a motion for summary judgment, disputed issues of fact are resolved against the moving party -- here, petitioners. But the question of admissibility of expert testimony is not such an issue of fact, and is reviewable under the abuse of discretion standard.(12)The circuit court's "particularly stringent," pro-admission standard was indeed short-lived.
In concluding that the district court did not abuse its discretion in excluding the plaintiff's experts, the Supreme Court examined the adequacy of the expert testimony the plaintiff sought to introduce to prove causation. The plaintiff's experts relied heavily upon animal studies to establish proof of causation in humans. The Court found, however, that the plaintiff failed to establish enough of a foundation to support the admissibility of these studies:
Rather than explaining how and why the experts could have extrapolated their opinions from these seemingly far-removed animal studies, respondent chose "to proceed as if the only issue [was] whether animal studies can ever be a proper foundation for an expert's opinion." Of course, whether animal studies can ever be a proper foundation for an expert's opinion was not the issue. The issue was whether these experts' opinions were sufficiently supported by the animal studies on which they purported to rely. The studies were so dissimilar to the facts presented in this litigation that it was not an abuse of discretion for the District Court to have rejected the experts' reliance on them.(13)Finally, the Supreme Court went on to suggest that it was not an abuse of discretion for the district court to demand a closer relationship between the epidemiological studies offered by the plaintiffs and the opinions drawn from them by the experts:
A court may conclude that there is simply too great an analytical gap between the data and the opinion proffered. See Turpin v. Merrell Dow Pharmaceuticals, Inc. 959 F.2d 1349, 1360 (CA 6), cert. denied, 506 U.S. 826, 121 L. Ed. 2d 47, 114 S. Ct. 84 (1992). That is what the District Court did here, and we hold that it did not abuse its discretion in so doing.(14)Upholding a judge's right to exclude given expert testimony on the basis of perceived analytical gaps in the science is an unprecedented broadening of the gatekeeper role. Such a ruling at first seems to run contrary to the "liberal thrust" of the Rules of Evidence as articulated in Daubert. It remains to be seen whether courts will be as deferential when judges exercise their discretion in favor of admissibility of arguably questionable scientific evidence. It is against this backdrop of federal case law that Alaska has fashioned her own approach to admissibility of expert testimony.
Pulakis v. State: Alaska
Embraces Frye General Acceptance
This is not to say that the worth of polygraph evidence cannot ever be proved to the satisfaction of the court. Two approaches which courts might find persuasive are (1) surveys of the opinions of experts familiar with polygraphs as to their usefulness in detection of deception, and, (2) experiments yielding meaningful data on the accuracy of polygraph examiners' opinions as to the veracity of the examinees.(18)Employing this two-step framework the court found that "we are not prepared to say whether polygraph examiners' opinions are reliable. Judicial acceptance of polygraph tests must await the results of more persuasive experimental proof of reliability."(19) Accordingly, the Pulakis court ruled that such evidence "should not be received in evidence over objection."(20) Moreover, the court defined a more activist gatekeeping role for trial judges by instructing them that "[e]ven if no objection has been tendered, the trial court ordinarily should reject [polygraph] evidence."(21)
Despite such uneasiness with polygraph evidence, the court found that Pulakis' attorney had waived any potential objections to the polygraph's admissibility.(22) Noting that the plain error rule was inapplicable where failure to object at the trial level was an intelligent waiver of a known right, the Pulakis court upheld the conviction.(23) Even had the plain error rule applied, the court was confident that polygraph tests were not "so demonstrably unreliable as to require a finding of plain error even in the circumstances of the record in the case at bar."(24) While this ruling proved to be of little help to Pulakis, it did set the course for admissibility of expert testimony in Alaska for the next twenty-nine years.
Contreras v. State: Pulakis
and the Rules
Evidence Rule 104(a)(26) assigns to the trial court the duty to determine preliminary questions concerning the qualification of a person to be a witness and the admissibility of evidence. Evidence Rule 401(27) defines what evidence is relevant. Evidence Rule 403(28) allows exclusion of relevant evidence for such reasons as prejudice, confusion, and waste of time. Evidence Rule 702(29) allows experts to offer helpful opinion testimony. Evidence Rule 703(30) allows experts to base opinions on facts or data of a type reasonably relied upon by experts in the field.(31)How the enactment of these rules would effect the general acceptance standard remained in question for the next seven years.
In 1986 the Supreme Court of Alaska held in Contreras v. State(32) that the Alaska Rules of Evidence did not supplant general acceptance as the rule for admissibility of expert testimony.(33) In Contreras the state supreme court overruled a court of appeals decision to admit hypnotically adduced testimony that led to a conviction for kidnapping and sexual assault.(34) Basing its decision on the Frye standard, the court ruled that this particular hypnotically adduced testimony was inadmissible.(35) The court did provide an exception to this rule that allowed "a witness who has been previously hypnotized to testify only to facts which he related prior to hypnosis."(36) This was, however, of little help to the prosecution in Contreras.
Chief Justice Rabinowitz writing for the majority indicated that applying Frye required a two-step approach:
First, the relevant scientific community must be defined, and, second, the testimony and publications of the relevant experts in the field must be evaluated to determine if there is general consensus that hypnotically adduced testimony is reliable.(37)Having determined the relevant scientific community, the state supreme court went on to analyze whether there existed general consensus within this community as to the reliability of hypnotically adduced testimony. First, the court defined its task as a rather passive endeavor:
[I]t is not this court's duty to decide which side of the debate is correct, but rather to determine if there is sufficient consensus on the reliability of hypnotically aided recall to determine whether it is generally accepted.(41)After considering "the hypnosis literature as reviewed by the litigants and as set out by the court of appeals,"(42) the court found "no consensus as to what hypnosis is or what it actually does."(43) Although the court found insufficient evidence to support either side's claims as to the benefits or dangers of hypnosis, it did indicate that "it is quite clear that the previously hypnotized witness may be prey to the distortions wrought by suggestion, confabulation, and increased confidence."(44) In the end, the "science" of hypnosis was far too underdeveloped to meet Frye muster.(45)
The State spearheaded the attack on the applicability of Frye in Contreras. The court began its defense of Frye by noting:
There are four reasons why the Frye "general acceptance" standard is appropriate when reviewing the admission of new types of scientific evidence: 1) the standard is judicially manageable; 2) the standard saves judicial time and resources; 3) the standard assures that juries will not be misled by unproven, unsound "scientific" procedures, thus safeguarding the court's truth-finding role; and 4) the standard assures fairness and uniformity of decision-making.(46)The court next addressed the State's argument that Frye could be used to exclude ordinary eyewitness testimony. The court reasoned that conventional memory refreshing devices used for eyewitness testimony are unlike hypnosis in that they do not potentially alter the subject's memory and demeanor the way hypnosis does.(47) Moreover, the court argued that the fact that "some traditional forms of evidence may have problems qualifying under Frye should not prevent Frye's application to new forms of evidence that are indisputably problematic, such as hypnosis."(48) Fearing that a jury ignorant of the "science" of hypnosis would be unable to judge the credibility of a witness giving hypnotically adduced testimony, the Chief Justice analogized this evidence to polygraph evidence thus cementing the need for Frye analysis.(49)
The State's final argument against the application of the Frye rule was that it had been supplanted by the Alaska Rules of Evidence. This argument centered on the fact that the Federal Rules, and by extension the Alaska Rules, did not incorporate or even mention Frye; thus, Frye was no longer the law of the land.(50) The Contreras court dismissed this assertion briefly:
We believe it unlikely that this silence was meant to overturn long-established rules of admissibility based on Frye such as the rule excluding polygraph testimony. Moreover we have held other pre-existing rules to survive adoption of the rules of evidence.(51)Additionally, the court noted that as other "[f]ederal and state courts with evidence rules adapted from the federal model have continued to apply Frye,"(52) there was no need to question Frye.(53) With that, the Supreme Court of Alaska ensured Frye's continued viability for the next thirteen years.
State v. Coon: Goodbye
Whether to adopt a new standard for admitting evidence involves the interpretation of the Alaska Rules of Evidence and is therefore a legal question to which this court applies its independent judgment, adopting the rule most persuasive "in light of reason, precedent and policy."(55)Prior to Coon, the state supreme court had chosen not to engage in this inquiry although it had recognized the existence of Daubert a full five years earlier in Mattox v. State, Department of Revenue.(56) Apparently, Coon was just the chance the court was looking for to lay to rest any concerns over Frye and the Alaska Rules.
At first glance, Coon does not appear to be the proper vehicle for reaching the issue of Frye's continued validity in Alaska. As the court mentioned, the Frye issue need not have been reached in Coon:
Because the trial court found Cain's opinion evidence to be admissible under both tests, and assuming that it applied each test correctly, it can be argued that there is no reason for us to resolve a legal issue that is not dispositive of the outcome of this petition.(57)Regardless of this assertion, the court felt it wise to proceed with its investigation. Citing its rule-making responsibility, the skillful discussion of the issues by the parties and amici, and its belief that delay would not produce better advocacy, the court chose to address the Frye/Daubert issue.(58) With that, the battle was joined over what standard of admissibility should be used in Alaska.
The court first addressed whether the federal and state constitutional prohibitions on ex post facto laws barred the application of the 1993 Daubert decision to Coon's 1992 trial.(59) Noting that the federal and state prohibitions apply only to legislative acts, not to judicial decisions, the court rejected Coon's argument out of hand.(60) Additionally, the court indicated that even if the ex post facto prohibitions were applicable, changes to rules governing the admissibility of evidence do not violate them; rather, these prohibitions apply only to "penal legislation."(61)
Having addressed the ex post facto issue, the Coon court next took up the State's arguments against Frye. The court framed the State's claims as follows:
[The State] argues that we should abandon the Frye standard. It asserts that Frye has become outdated and inadequate for modern litigation, where many cases involve sophisticated scientific data and knowledge. It argues that Frye uses social, rather than scientific, criteria for determining reliability and validity when reviewing a novel scientific technique. This causes trial courts simply to "count hands" to determine whether scientists in the relevant scientific community accept the technique as reliable, and "abdicates" judicial responsibility for determining admissibility to scientists uneducated in the law.With these arguments in mind the Coon court examined the evidentiary framework available to them in the absence of Frye, namely, the Alaska Rules of Evidence.
Citing the appropriate provisions of the Alaska Rules of Evidence, the Coon court explained why the State was correct in asserting that Frye was unnecessary in light of the rules and Daubert. Under the Alaska Rules of Evidence expert opinion evidence is admissible:
[I]f the trial court (exercising its authority under Rule 104(a)) determines that (1) the evidence is relevant (Rule 401); (2) the witness is qualified as an expert (Rule 702(a)); (3) the trier of fact will be assisted (Rule 702(a)); (4) the facts or data on which the opinion is based are of a type reasonably relied upon by experts in the particular field in forming opinions upon the subject (Rule 703); and (5) the probative value of the evidence is not outweighed by its prejudicial effect (Rule 403).(63)Key to this framework is the fact that none of the cited rules suggest that any single criterion, including general acceptance, should control admission of scientific opinion evidence.(64)
According to the court, the commentary to Rule 703 suggests that general acceptance should not be the only standard for admissibility "[Rule 703] attempts to chart a path between the rigid approach of [Frye] and the minimal relevance approach of Rule 401."(65) Additionally, the Court highlighted the list of "Daubert-like" factors mentioned in the commentary to Rule 703 as a strong indication that general acceptance should not be the trial court's only concern.(66) These factors included the rate of error associated with the proffered scientific technique along with a general unwillingness to resolve issues of particular controversy among the nation's experts.(67) Ultimately, the Coon court found these factors and the rules' silence as to Frye to weigh heavily in favor of adopting "a broader inquiry, allowing a proponent to establish admissibility even if general acceptance is absent, and allowing an opponent to challenge admissibility even if general acceptance is present."(68)
Underlying this desire to expand upon the Frye standard was the belief noted in Daubert and agreed to in Coon that Frye was potentially both overinclusive and underinclusive in admitting relevant evidence. As the court remarked in Coon:
Frye is potentially capricious because it excludes scientifically reliable evidence which is not yet generally accepted, and admits scientifically unreliable evidence which although generally accepted, cannot meet rigorous scientific scrutiny. Because the Frye test potentially excludes evidence that should be admitted under our rules, and also potentially admits evidence that should be excluded under our rules, we conclude that it is both unduly restrictive and unduly permissive.(69)Insofar as the U.S. Supreme Court found this reason persuasive enough to rule that Frye was inconsistent with the Federal Rules of Evidence; so, too, did the Supreme Court of Alaska find it persuasive enough to rule that Frye was inconsistent with the Alaska Rules of Evidence.(70)
In deciding to eschew Frye in favor of a broader standard of admissibility, the Coon court faced the unenviable task of overruling Contreras. In order to overrule one of its own prior decisions the Supreme Court of Alaska employs the following standard:
We have stated that we will overrule a prior decision only when we are "clearly convinced that the rule was originally erroneous or is no longer sound because of changed conditions, and that more good than harm would result from a departure from precedent."(71)The court found that both aspects of this test were met.
The court reasoned that the assumption in Contreras that the Federal Rules of Evidence did not change Frye was clearly erroneous.(72) The Coon court noted that Daubert, itself, disproved this assumption.(73) Next, the court cited the "reasonably relied upon by experts" wording of Rule 703 for the proposition that general acceptance was not the only standard envisioned by the framers of the rules.(74) Finally, the court asserted that the commentary to Alaska Rule 703 specifically indicated an intent to "chart a path between the rigid approach of [Frye] and the minimal relevance approach of Rule 401."(75)
Once the Coon court established that Contreras was based on clearly erroneous assumptions, it addressed whether more good than harm would come from overruling the decision. The court began by reiterating its fears that Frye excluded some scientifically reliable evidence while admitting unreliable evidence.(76) Next, the court opined that any potential harm from changing the standard would arise only in the small number of cases in which the Frye/Daubert issue was currently pending in a trial court or was on direct review at the appellate level.(77) Although this might force some retrials when the change produced more than harmless error, the Coon court seemed confident that such new trials would be rare.(78) Ultimately, the court concluded that "it is better to resolve admissibility disputes by referring to our modern evidentiary foundation, the Alaska Rules of Evidence, than by trying to salvage or remold a 'rigid' standard that is fundamentally inconsistent with our rules."(79) With these concerns in mind, the court went on to explain its vision for the post-Frye admissibility world.
In place of Frye, the Coon court advocated a Daubert-based series of admissibility factors. Borrowing heavily from the U.S. Supreme Court, the state supreme court noted:
How should Alaska trial courts assess the reliability and relevance of proffered scientific evidence? The factors identified in Daubert provide a useful approach: (1) whether the proffered scientific theory or technique can be (and has been) empirically tested (i.e., whether the scientific method is falsifiable and refutable); (2) whether the theory or technique has been subject to peer review and publication; (3) whether the known or potential error rate of the theory or technique is acceptable, and whether the existence and maintenance of standards controls the technique's operation; and (4) whether the theory or technique has attained general acceptance.(80)Additionally, the Coon court looked to the Ninth Circuit's reasoning in Daubert on remand for additional factors:
[T]he Ninth Circuit suggested two ways to satisfy Daubert's requirement that the testimony be "derived by the scientific method [or] . . . based on scientifically valid principles." As described by Kesan, "either (a) the expert's proffered testimony must grow out of pre-litigation research, or (b) the expert's research must be subjected to peer review." Kesan, giving the example of "independent" research funded by tobacco companies appropriately notes the danger of a hidden litigation motive. Nonetheless, publication is at least more likely to provoke scrutiny and response, and reveal methodological deficiencies.(81)Finally, the Coon court noted that a number of other states with rules similar to Alaska's had been successful with such Daubert-based approaches.(82)
The court began its defense of Daubert by systematically listing and then debunking a series of arguments against Daubert. The first such argument was that Daubert is unduly burdensome on trial judges.(83) The court defined this concern as "founded on a perception that Daubert requires judges to determine the reliability of the expert's scientific methods, whereas the general acceptance standard allows courts to defer to the judgment of scientists."(84) The court dismissed the inherent appeal of having scientists judge scientific reliability under Frye by noting that general acceptance does not define scientific reliability.(85) According to the state supreme court, Frye general acceptance was no more than a "judicial construct" with obvious flaws.(86) Next, the court emphasized that trial judges, not scientists, should enforce the rules of evidence subject to review for abuse of discretion.(87) To this end the Coon court stressed that Frye's delegation of judicial authority to experts' peers was unacceptable.(88)
After establishing that judges must bear the burden of determining what evidence is reliable in the courtroom, the court suggested that this burden, though all too real, was none too great. The court based this assertion on its belief that:
[M]ost difficult disputes will be limited to evidence that is rationally disputable; we expect that relatively little effort will be required to determine the admissibility of most scientific evidence, because most will be either patently reliable or unreliable.(89)For those rare difficult situations, the Coon court noted that trial judges were empowered to select their own independent expert witnesses and even to appoint expert advisors.(90)
Once it had addressed these undue burden arguments, the court moved on to answer the claims of several amici who argued that Daubert opened the courts to "junk science."(91) These opponents of Daubert reasoned that Frye's more restrictive general acceptance test prevented juries from being misled by unreliable but highly persuasive "junk science."(92) In response, the Coon court noted that the Frye standard was no better protection and easily could be manipulated to admit or exclude particular evidence.(93) Moreover, the court saw no evidence that in other states using Daubert there had been a flood of "junk science" in the courtrooms.(94) According to the court, "post-Daubert reported decisions suggest that courts are acting with restraint, and are giving rigorous consideration to the reliability of scientific evidence."(95) Finally, the court reiterated its belief that Frye is prone to admitting unreliable scientific evidence as well.(96)
The final argument leveled against Daubert concerned relitigation of evidence admissible under Frye. According to this argument:
[T]he Daubert standard applies to all scientific knowledge, and is not limited to "novel" scientific evidence, evidence deemed admissible under Frye may now be found inadmissible under Daubert. . . . this will lead to increased litigation over the admissibility of scientific evidence, and to a case-by-case determination of admissibility, with the possibility of inconsistent of unpredictable decisions.(97)In response, the justices noted first that courts can curb such relitigation by taking judicial notice of the admissibility of well-known areas of expertise.(98) Next, the court reasoned that because general acceptance remained a factor under Daubert the possibility of relitigation was tempered.(99) Finally, the court expressed doubts that any methodology that had met Frye muster and remained generally accepted would be excluded absent affirmative evidence of unreliability.(100) Having dispelled these criticisms of Daubert the court turned its attention to whether the trial court had applied Daubert correctly.
As a preliminary matter the court debated the proper standard of review to adopt for Daubert decisions. According to the majority in Coon, abuse of discretion was the proper standard of review for issues of admissibility.(101) Conversely, certain scholars and the dissent in Coon argued for a hybrid standard of review:
Kesan, and the dissenting opinion proposed adopting a hybrid standard of review, reviewing de novo a trial court's findings on the scientific knowledge prong of the Daubert test and retaining an abuse of discretion standard for the second prong relating to relevance or "fit" of the facts of the particular case to the scientific technique employed. They assert that implementing de novo review of scientific validity allows for more uniform adjudication at the trial and appellate levels, and for development of distinct validation criteria for expert testimony relating to different scientific or technical disciplines.(102)The majority stressed both that such evidentiary issues are historically reviewed for abuse of discretion and that the risk of inconsistency was not as great as the dissent contended.(103) The majority noted then that despite academics' grave predictions that abuse of discretion review would undermine judicial integrity, the majority of the Federal Circuits and the U.S. Supreme Court had embraced the abuse of discretion standard.(104) Accordingly, the court held that abuse of discretion best comports with its desire to ensure "greater flexibility in determining the admissibility of expert testimony, so as to keep pace with science as it evolves."(105) In the end, Coon firmly established that Daubert and the Alaska Rules of Evidence had supplanted Frye as the guiding principle for determining issues of admissibility for scientific evidence and that the state's appellate courts would apply an abuse of discretion standard in reviewing decisions under Daubert and the Rules.
F. 1013 (D.C. Cir. 1923).
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