The use of expert witnesses in litigation is something all litigators know to be commonplace. Some estimates suggest that roughly 30% of ALL federal cases use experts. Some types of cases (mass torts, environmental law, etc.) have almost mandatory requirements for using expert witnesses.
Litigators also know that a good expert has a couple of essential traits that really go beyond the actual expertise. An expert must be credible to a jury, who, in complicated cases, may not fully understand the science being presented but still must make a decision of enormous consequence. In the same vain, the expert must be confident in the courtroom. Juries generally find waffling and imprecise explanation to be a bad sign, and accordingly discount that expert’s testimony.
Yet, a third, and perhaps most critical, factor can make a difference in a jury’s perception of expert testimony: bias. How does a jury come to terms with two experts who disagree on fundamental questions and who they know is being paid to testify by a party? Indeed, it is precisely this bias that makes credibility and confidence valuable – juries have no other way of “breaking the tie.”
A 2012 study by Christopher Robertson and David Yokum, from the University of Arizona and Harvard University, attempts to address this adversarial bias head-on by using “blinded experts.” In short, “at the request of a litigant, an intermediary selects a qualified expert and pays the expert to review a case without knowing which side requested the opinion.” Many questions arise in the use of such an expert. What happens if the expert comes to an unfavorable opinion? Why would a party pay for such a service when the outcome is uncertain? What benefits are actually derived from blind expertise? Do the odds of winning increase? Do jury awards change?
The study by Robertson and Yokum answer all of these questions – and then some:
Mechanics aside, however, the question of the cost/benefit analysis that would justify such an expert still remains. This was the subject of the study. In brief, 275 mock jurors were asked to watch a video of a staged medical malpractice trial whereby experts were either unblinded (control condition), or blinded for either the plaintiff or defendant. The study found that in blinding the expert, the odds of a favorable verdict was doubled. Even better, the damages awarded by the juror was increased (or decreased) by $100,000+. The study details can be found in the paper.
The trends expressed by these results are not surprising, but the magnitude of the effect might be. Most good litigators know that the “hired-gun” is the last thing they need for their case. Yet, without a clear signal of neutrality (i.e. such as blinding), it may be impossible for a jury to understand who is correct and who is not. Rigorous cross-examination is of course used as the traditional method to undermine an expert’s credibility, but both sides use this tactic and therefore are unable to break the expert testimony “tie.” However, by doubling the chances of victory and swinging damages by $100,000+, “blinding” may just be the tie-breaker that litigators have been looking for.