Interesting Case on Admissibility of Expert Testimony in Bench Trials: A Circuit Split

By David Hricik, Mercer Law School

I serve on occasion as an expert witness in patent-related trials, on inequitable conduct and the standard of care in malpractice.  Of interest to me for that reason and because I still do lawyering work is UGI Sunbury LLC v. A Permanent Easement for 1.757 Acres (here) a 2019 Third Circuit decision holding that the same standard under Daubert/Kumho Tire governing admissibility of expert testimony in jury trials applies to bench trials where the trial court is the fact-finder. Specifically, while the court recognized trial courts have discretion as to how to admit expert testimony and use it, the court cannot admit unreliable expert testimony in the first instance, even when it is a bench trial.  This presents a circuit split (note 4 of the opinion collects some of the contrary opinions).

Of course, the case should be of interest to patent litigators, since for example inequitable conduct may present only issues for the court.  In that context, I have seen opposing experts use “methodologies” that they would never apply practice or defend in public, and use “methodologies” that — at least in my experience, education, and training — are unverifiable and unreliable.

A more rigorous approach to expert witness testimony may help to avoid needless confusion and wasted time — even in bench trials.

About David

Professor of Law, Mercer University School of Law. Formerly Of Counsel, Taylor English Duma, LLP and in 2012-13, judicial clerk to Chief Judge Rader.