Barthel: Does Accuracy of WCJ Credibility Assessments Justify Using Them as Lie Detectors?

Wednesday, July 15, 2026 | 0

How well can judges assess a witness’s credibility, and how important does the WCAB believe it is for a WCJ to have the opportunity to apply its presumably well-honed baloney barometer? The answers may surprise you.

Donald R. Barthel

The Workers' Compensation Appeals Board firmly believes judges can assess honesty in the courtroom. Presumably, this is due in no small part to the commissioners’ prior careers on the bench. After years of judging witness veracity in the courtroom (and rarely, if ever, having their judgments successfully challenged), the commissioners have likely been presented with little or no evidence that their assessments are suspect.

The WCAB’s respect for the “science” of credibility assessment has a long history, extending as recently as 2026. In Orozco v. County of Monterey, neither party called witnesses to testify, choosing instead to submit offers of proof setting forth what the witnesses would have said. Based on those offers, the workers' compensation judge found sufficient evidence to conclude that the claim was timely filed.

Incredibly, the ruling was appealed to the WCAB, which concluded that the WCJ lacked substantial evidence to make the necessary credibility determination. Without the opportunity to observe the witnesses’ demeanor and presentation, the WCJ could not determine whether the witnesses were worthy of belief.

A judge’s ability to assess credibility is drilled into law students during their first year of law school. This continues throughout the practice of law and, as suggested above, during service as WCJs and later as WCAB commissioners. But does science justify this long-held confidence in the WCJ’s baloney barometer?

Are WCJ's credibility assessments dependable?

In a word, science answers with an emphatic “no.”

When it comes to spotting deception, judges perform only marginally better than non-judges. The definitive meta-analysis on this topic, conducted by researchers Charles Bond Jr. and Bella DePaulo, synthesized data from more than 24,000 participants across 206 studies and found that the average person’s deception-detection accuracy rate is approximately 54%. (Source: Charles F. Bond Jr. & Bella M. DePaulo, Accuracy of Deception Judgments, 10 Personality & Social Psychology Review 214 (2006).)

Extensive psychological and legal research likewise reveals that judges are not significantly better at detecting lies than the average person. Decades of studies — including classic research by deception expert Paul Ekman and subsequent studies of judges and other legal professionals — demonstrate that when separating truth from deception based solely on a witness’s testimony and demeanor, judges typically score only slightly above chance, approximately 54% to 60% accuracy. A coin flip, by comparison, is 50%. (Ekman, P. (2009). Telling Lies: Clues to Deceit in the Marketplace, Politics and Marriage (4th ed.). W.W. Norton.)

What's the problem?

Both judges and non-judges struggle for essentially the same reason: They look for the wrong cues.

The average person relies heavily on visual stereotypes of deception. They assume a liar will avert eye contact, fidget, touch their face or stutter. In reality, decades of behavioral science have demonstrated that these cues are highly unreliable. A nervous but truthful witness often appears indistinguishable from a nervous liar. Conversely, experienced deceivers frequently maintain steady eye contact and carefully control their body language because they know exactly what observers expect to see.

The upshot

Although your WCJ may believe they can assess credibility by looking for sweating palms and shifty eyes, you know better. Moreover, such cues are notoriously unreliable. A witness who appeared nervous or evasive during deposition may arrive at trial thoroughly prepared and far more polished. The baloney barometer can easily be fooled.

Fortunately, credibility in workers’ compensation cases rarely depends on demeanor alone. The strongest credibility determinations arise when testimony is tested against objective evidence.

Be prepared to highlight:

• Inconsistencies between hearing testimony and medical records.
• Differing histories provided to treating physicians, QMEs and AMEs.
• Surveillance or properly admitted social media evidence.
• Personnel, payroll and attendance records.
• Contemporaneous emails, text messages and other business records.
• Objective medical findings that either support or contradict the witness’s account.

These time-tested methods are far more dependable than attempting to read body language or facial expressions.

So have fun demonstrating that your opponent’s witness is delivering testimony worthy of this year’s Pinocchio Award. Just don’t expect the witness’s nose to do the work for you.

Donald R. Barthel is a founding partner of Bradford and Barthel and is based in the firm’s Sacramento office. This entry from Bradford & Barthel's blog appears with permission.