Rule 702 of the Federal Rules of Evidence governs the admissibility of expert opinion testimony in federal court. Indeed, the admissibility of expert opinion testimony is a key driver of the outcome in a multitude of criminal and civil proceedings. In the absence of admissible DNA or fingerprint evidence, a prosecutor may make an attractive plea offer. Without an admissible expert opinion, a plaintiff in a toxic tort or products liability action will be unable to survive a defense motion for summary judgment. Thus, the standard for admitting expert opinion testimony remains of critical importance to the resolution of both criminal and civil cases in federal court. Rule 702 has seen several updates and modifications since it was first enacted, starting with the Supreme Court’s landmark interpretation of the Rule in 1993 in Daubert v. Merrell Dow Pharmaceuticals, Inc. In that case, the Supreme Court cemented the trial judge’s role as “gatekeeper” to ensure that unreliable expert opinion testimony is not presented to a lay jury. But Rule 702 has been amended twice since the Daubert opinion to clarify and even to expand the role of the trial judge in regulating the admissibility of expert opinion testimony, most recently on December 1, 2023.
Rule 702, as recently amended, contains several threshold admissibility requirements that the proponent of an expert witness must demonstrate to the court by a preponderance of the evidence before presenting the expert to the jury. Our review of every published federal district court opinion interpreting these important admissibility requirements in the year since Rule 702 was amended reveals that the amendment has made great strides in ensuring that unreliable expert opinion testimony does not reach the jury. Some federal courts have applied the new Rule in its first year carefully and appropriately. Still, there is further progress to be made in applying Rule 702 as intended to ensure that jurors are shielded from unreliable expert opinion testimony that they lack the experience to evaluate effectively. Many litigants continue to rely upon outdated case law, such as the decades-old Daubert opinion itself, to support the admissibility of expert opinion testimony. The Daubert Court sent some mixed signals about a trial judge’s duty to police “shaky” expert testimony, and this dicta has been deployed to allow testimony through the gate that is inadmissible under current Rule 702. And some federal courts continue to cite precedent that predates one or both of the amendments to Federal Rule of Evidence 702 since Daubert was decided to support admissibility determinations that are inconsistent with its current mandate. Relying upon and applying amended Rule 702 faithfully is crucial to the goals of the Federal Rules of Evidence to “ascertain[] the truth” and “secur[e] a just determination” in complex cases in federal court.
To read this Article, please click here: The Difference a Year Makes: The Admissibility of Expert Opinion Testimony Under the 2023 Amendment