Few areas of law depend to a greater degree on expert testimony and evidence than litigation involving environmental law and toxic torts. Verdicts in such cases often turn on the credibility that the judge or jury affords a particular expert witness and his opinion. Thus, it is usually critical that a litigant in such a case have his own expert's opinion accepted by the court under the appropriate evidentiary standards, while at the same time arguing that the opposition's conflicting expert opinion does not meet the threshold of the standard for admissibility.
The importance of this evidentiary issue is amply reflected in the fact that, in the last six years, the United States Supreme Court has granted certiorari for appellate review of three cases that each deal with the standard of admissibility for expert testimony. To appreciate the significance of the high court's actions, it must be understood that the Court accepts relatively few of the many cases for which review is sought, choosing only those it considers of suitable import based on constitutional and policy concerns. Thus, the Court's trio of visitations in such a short time span to this evidentiary issue of the admissibility of expert opinion is remarkable.
Until 1993, the prevailing expert evidentiary standard was taken from the longstanding decision in Frye v. United States, 293 F. 1013 (D.C. Cir. 1923), which required that a scientific theory only be generally accepted in the relevant scientific community to serve as a basis for expert opinion. But with the adoption of the modern Federal Rules of Evidence in 1975, the Supreme Court stated that the focus of expert opinion was statutorily altered, warranting a different standard to test admissibility. In the case of Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), the Court stated that federal courts should decide the issue of the admissibility of expert scientific opinion by the application of five factors:
- Whether the expert's theory has been or can be tested for validity;
- Whether the theory has been subject to peer review and publication;
- The known or potential rate of error when the theory is applied;
- The existence and maintenance of standards of control; and
- The degree to which the theory is accepted in the scientific community. Id. at 593-95.
The federal trial courts are to apply these factors as a matter of a "gatekeeping" role to assure that expert opinion be both relevant and reliable to assist the trial court or jury in rendering a decision. While the Court noted that the new rules of evidence are premised on a more liberal evidentiary thrust, these factors have served in practice under Daubert and the cases which have followed it to limit expert opinion to valid scientific theories and to weed out junk science. The federal trial courts are to apply these factors as a matter of a "gatekeeping" role to assure that expert opinion be both relevant and reliable to assist the trial court or jury in rendering a decision. While the Court noted that the new rules of evidence are premised on a more liberal evidentiary thrust, these factors have served in practice under Daubert and the cases which have followed it to limit expert opinion to valid scientific theories and to weed out junk science.
After the Daubert decision, the Court considered as a separate issue in the case of General Electric Company v. Joiner, 522 U.S. 136 (1997), whether a different standard should apply in allowing expert opinion into the record as opposed to excluding admissibility. In that case, the lower circuit appeal court ruled that, while a trial court's decision to admit expert opinion is to be reviewed on the "abuse of discretion" standard, a court's exclusion of such evidence should be weighed against a "particularly stringent standard of review." However, the Supreme Court again emphasized that the trial court as "gatekeeper" is required to make the fundamental determination as to whether there is an adequate nexus between the data presented and the opinion posed, or instead is a connection borne only of the "ipse dixit" (he himself said it) of the expert's baseless assumptions. Whether the trial court admits or excludes the evidence in this role, the Court held that the decision is subject solely to the "abuse of discretion" standard as a matter of review.
The last case in the "Daubert trilogy" is the Court's recent decision in Kumho Tire Co. v. Carmichael, 1999 U.S. LEXIS 2189 (March 23, 1999). In that case, the issue was whether the Daubert factors are to be applied only in cases where expert opinion deals with purely scientific principles or, instead, are equally applicable in other areas of technical expertise. The expert's testimony in Kumho concerned a general theory as to the reason an automobile tire had failed, resulting in a severe accident. Using the Daubert analysis, the trial court excluded this form of engineering testimony as unreliable, but was reversed by the lower appellate court. The Supreme Court reinstated the trial court's determination, stating that the Daubert factors were equally applicable to engineering testimony - and to all forms of expert testimony - to the degree that each factor was relevant in considering the particular expert opinion.
Since the Daubert decision, the United States Fifth Circuit Court of Appeal, which reviews cases arising in Louisiana's federal district courts, has considered a number of cases in which it has applied the Daubert factors. Two of the most recent decisions are Moore v. Ashland Chemical, Inc., 151 F.3d 269 (5th Cir. 1998) and Black v. Food Lion, Inc., 171 F.3d 308 (5th Cir. 1999).
In the Moore case, a truck driver claimed to have suffered a permanent lung dysfunction due to short-term exposure to a toluene-based chemical spill. One of his expert physicians was to testify that the specific lung illness was a condition termed "reactive airways dysfunction syndrome." Though the physician expert was recognized as a respected and distinguished practitioner in the field of pulmonary medicine, he could not show a credible scientific link to toluene exposure and the diagnosed disease. While the Fifth Circuit Court panel of three judges reversed the trial court's exclusion of the evidence, the appeal court granted rehearing to consider the matter en banc. Relying heavily on the Joiner case, the court then held that the trial court had not abused its discretion in finding that the expert's opinion was unreliable, as based either on conjecture or inadequate evidence, in posing that the plaintiff's specific illness was linked to a short-term exposure to toluene.
Similarly, in the Black case, the plaintiff claimed that a slip and fall incident in defendant's store caused trauma resulting in the disease "fibromyalgia," characterized by generalized pain, poor sleep, loss of concentration, and chronic fatigue. As the Kuhmo Tire case had been decided by the Supreme Court upon hearing of this matter, the appeal court first noted that under that case the Daubert factors were unquestionably relevant to the admissibility of the expert physician's medical diagnosis. The magistrate judge at trial of a defense motion to exclude the diagnosis allowed the expert physician to offer her conclusion into evidence, but did not specifically apply the Daubert factors in more than a generalized manner. In reversing the magistrate's decision, the Fifth Circuit noted that the magistrate had not applied the factors with specificity to test the expert's physician's methodology of determining that the plaintiff's trauma could have caused the diagnosed condition. Though the physician attempted to rule out other causes for the disease, relevant medical literature indicated no causative link between trauma and contraction of plaintiff's condition. In the court's opinion, had the magistrate conducted a proper analysis under Daubert and Khumo Tire, "the utter lack of any medical reliability of [the physician expert's] opinion would have been quickly exposed."
Lastly, and most significant in litigation in the state's courts, the Louisiana Supreme Court, in State v. Foret, 628 So. 2d 1116 (La. 1993), adopted the Daubert standard for testing expert testimony nearly immediately after it was articulated. Noting that Sections 702 of both the federal and the Louisiana evidence codes pertaining to the admissibility of expert opinion are identical, the state supreme court stated that it should follow Daubert on the same reasons stated therein. In Foret, the criminal defendant had been convicted of sexual abuse of a minor, based in part on the expert testimony of a child psychologist. The psychologist used an interview technique, developed for diagnosing the effects of child abuse to prescribe appropriate treatment, as a basis for an opinion that the victim's interview responses positively indicated she had been abused. But, the court cited to literature that stated the technique was unreliable in delineating actual abuse from fantasy or fraud, and was accepted as valid only for its intended purpose. Based on the Daubert factors, while the court did not exclude the testimony of its own accord, it remanded the case for a new trial with the admonition that the trial court exercise its "gatekeeping" authority to closely evaluate any such testimony offered at retrial.
To date, Daubert has been cited in reported Louisiana state court cases 43 times. The most recent citation is in State v. George, 1999 LEXIS 447 (La. Feb. 26 , 1999), where the court sided with the trial court's exercise of the "gatekeeping" function to exclude evidence of defendant's alleged "limbic psychotic trigger reaction," asserted as a justification for violent conduct.
As seen in the foregoing cases, the admissibility or exclusion of expert opinion after Daubert can be decisive in an environmental or toxic tort case. Of significance to Louisiana businesses, a bill currently is being considered in the legislature (HB 247) which would impose a "loser pays" rule as to legal fees and costs against plaintiffs who bring frivolous lawsuits. The above decisions indicate that a challenge to the expert basis of a case under the Daubert factors can be key in exposing baseless litigation. Should the legislature pass this bill, the "Daubert challenge" may well be one method used to test the relative merits of a matter alleged frivolous by the defendant.