The amended Federal Rules of Evidence (FRE) 702 regarding the admissibility of expert witness testimony in federal courts took effect on December 1, 2023. This article discusses how the recent changes could have significant implications for the role of expert testimony going forward.

Sardis v. Overhead Door Corp., 10 F.4th 268 (4th Cir. Aug. 20, 2021).

Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993).

Preponderance burden

The first amendment clarifies and emphasizes that expert testimony isn’t admissible unless the proponent establishes that it’s more likely than not that the testimony meets the rule’s admissibility requirements. In other words, the same preponderance of the evidence standard that applies to most of the FRE’s admissibility rules applies to the admissibility of expert testimony. In the past, many courts have mistakenly held that questions about the sufficiency of an expert’s basis and application of the expert’s methodology are questions of weight rather than admissibility.

The amendment reiterates that the preponderance standard applies to FRE 702’s reliability-based requirements. Many courts also have incorrectly evaluated these requirements under the more lenient FRE 104(b) standard instead of FRE 104(a).

The Advisory Committee on Evidence Rules criticizes courts for characterizing expert challenges as going to weight, not admissibility. But it acknowledges that some challenges do indeed raise matters of weight — even under the FRE 104(a) standard. For example, the fact that an expert with a sufficient basis to support an opinion hasn’t read every study on the issue goes to weight. But arguments about the sufficiency of basis don’t always go to weight.

More insight on the standard

According to the Advisory Committee, the amendment doesn’t require a court to make a finding of reliability in the absence of an objection. When reliability is assessed, a proponent must demonstrate only that expert opinions are reliable, not that they’re correct. And, when experts come to different conclusions based on contested facts, the FRE 104(a) standard doesn’t necessarily require exclusion of either side’s expert. By deciding the contested facts, the jury can decide which experts to credit.

The Advisory Committee also rejected the requirement of some courts that expert testimony “appreciably help” the trier of fact. It deemed this standard of helpfulness “unnecessarily strict” and reinforced that the expert’s knowledge is required only to “help” the trier of fact understand the evidence or determine a fact in issue.

Court gatekeeping duties

The second amendment to FRE 702 emphasizes that each expert opinion must stay within the bounds of what can be concluded from a reliable application of the expert’s basis and methodology. It’s up to the court to make this determination. Jurors who lack specialized knowledge may not be capable of meaningfully evaluating the reliability of scientific and other methods underlying expert opinions. They also might not be able to determine whether experts’ opinions go beyond what their basis and methods reliably support.

The Advisory Committee stresses that this amendment is particularly relevant to the testimony of forensic experts. These experts should avoid assertions of absolute certainty (or “to a reasonable degree of scientific certainty”) if their methodology is subjective. Where possible, judges should receive an estimate of the methodology’s known or possible rate of error — typically based on studies that reflect how often the method produces accurate results. Further, when expert opinion testimony includes evidence that a set of features corresponds between two examined items, the testimony must be limited to inferences that can reasonably be drawn from reliably applying principles and methods.

The amendment doesn’t require new or specific procedures. It also doesn’t require a court to “nitpick” an expert’s opinion to attain a perfect expression of what the basis and methodology can support. Although the FRE 104(a) standard doesn’t require perfection, it does prohibit experts from making claims unsupported by the basis and methodology.

A double-edged sword

Litigants should expect district courts to take a more stringent stance when it comes to expert witness testimony. So, take precautions to ensure your expert witnesses 1) are qualified, and 2) offer relevant and reliable testimony. On the flip side, with proper preparation, you may have greater success excluding opposing experts.

Early application of revised FRE 702 offers insights

The U.S. Court of Appeals for the Fourth Circuit relied on the amended Federal Rules of Evidence (FRE) 702 in 2021, even though they hadn’t yet been finalized. In Sardis v. Overhead Door Corp., the appellate court reversed a nearly $5 million verdict in a product liability case. It explained that the lower court abdicated its “critical gatekeeping role to the jury” by allowing testimony from two experts without engaging in the required analysis.

The district court didn’t perform any Daubert analysis and ruled that the issues of relevance and reliability affected only the weight of the experts’ testimony. It recognized “legitimate concerns” with one expert’s proffered testimony but deemed them solely a subject for cross-examination.

The appellate court found the lower court’s error harmful because, if the court had satisfied its Daubert responsibilities, precedent would have compelled the exclusion of both experts’ testimony. Without that testimony, the plaintiff failed to meet its evidentiary burden on each cause of action.

Contact us today to learn more about the amended Federal Rules of Evidence (FRE) 702.