Daubert's general holding-setting forth the trial judge's general "gatekeeping" obligation applies not only to testimony based on "scientific" knowledge, but also to testimony based on "technical" and "other specialized" knowledge. Fed. Rule Evid. 702. A trial court may consider one or more of the more specific factors that Daubert mentioned when doing so will help determine that testimony's reliability. But, the test of reliability is "flexible," and Daubert's list of specific factors neither necessarily nor exclusively applies to all experts or in every case. Rather, the law grants a district court the same broad latitude when it decides how to determine reliability as it enjoys in respect to its ultimate reliability determination.
Respondent customers brought a diversity suit against petitioner tire maker after a tire blew out on their minivan, causing the death of one passenger and leaving others injured. Respondents' expert in tire failure analysis intended to testify that a defect in the tire's manufacture or design caused the blow-out. The district court excluded the expert's testimony after an examination of Daubert's reliability-related factors, which renders admissible scientific expert testimony (1) if relevant and reliable; (2) the Federal Rules of Evidence (FRE) assigned to the trial judge the task of insuring that an expert's testimony rested on a reliable foundation and was relevant to the task at hand; and (3) some or all of certain specific factors--such as testing, peer review, error rates, and acceptability in the relevant scientific community--might possibly prove helpful in determining the reliability of a particular scientific theory or technique. The court of appeals reversed stating that since the expert’s testimony was based on experience, the test, which is limited limited to scientific testimonies, does not apply.
Whether the Daubert standard applies only to scientific testimony.
On appeal, the Court held that the Daubert standard of evidentiary reliability was not limited to scientific testimony but extended to all expert testimony. A trial judge could have considered Daubert's specific factors to assess reliability and to determine admissibility. However, the Court emphasized that while a trial judge may consider those factors, the factors may or may not apply in a particular case. The Court found that some of Daubert's questions were helpful in evaluating the reliability even of experience-based testimony. The Court concluded that refusal to admit the testimony of respondents' expert was not an abuse of discretion where no evidence existed that any other tire expert accepted the methodology of respondent's expert.