Redefining expert witness credibility for juries

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Juries routinely dismiss expert testimony due to credibility problems, incomprehensibility, or simply because it is cancelled out by another expert’s testimony.

This leads to a number of important questions for the attorney and the expert in presenting testimony at trial. What exactly is credibility? Is an expert an advocate? How objective is an expert supposed to be?

Normally, we discuss expert credibility in terms of how an expert’s background education, training and accomplishments compare with those of opposing experts, methodological concerns about how they arrived at their opinions, their “objectivity,” how much money they were paid or their demeanor while testifying. While all of these factors play a role in juror evaluations of an expert, there is one primary means of enhancing expert witness credibility: improving how that expert teaches the fact finder.

Good communication

In speaking with jurors in post-trial interviews and participants in mock trial debriefings, jurors’ negative descriptions of expert witness testimony (“arrogant,” “combative,” “inconsistent,” “confusing,” “slick”) reveal one fundamental problem with expert testimony: the lawyer and the witness did not have the intention of truly communicating with today’s jury.

The standard approach in direct examination is to take experts through their education and professional accomplishments, thus establishing their credibility. But given today’s harried and demanding juror, there is some inherent resistance to the structure of this testimony.

First, jurors have some skepticism about the objectivity of paid opinions. Second, although degrees, publications and general achievements in a field of expertise are important in the selection of experts, they are not the primary credibility characteristics for jurors. Third, jurors struggle with the density of technical testimony, whether it is about medical, engineering or other complex subjects.

In post-trial interviews and mock trials I have conducted across the country over the years, three characteristics are cited most frequently by jurors in positive reviews of expert testimony: experience that is relevant to the jury, the ability to use a methodology the jury recognizes and the ability to teach that methodology by communicating the resulting conclusions.

First, jurors are looking to see that an expert has personal and practical experience, as opposed to purely theoretical or academic expertise. For example, if an economic expert’s father ran a grocery store, he could tell jurors about watching him balance the books and keeping track of inventory.

Second, it is important to walk the jurors through a point-by-point re-enactment of the expert’s methodology. This allows jurors to see what the expert is seeing as he or she analyzes the subject matter, essentially making them the experts. It is also important to ask the expert what he was thinking as he looked at the data or results. This allows jurors to understand how the expert formed his final conclusions.

The final key characteristic in an expert’s testimony is the ability to communicate effectively.

A good teacher understands that a student needs context in order to appreciate the significance of an opinion or finding. The more complex the litigated subject, the more jurors (and judges) look to the expert to give them a framework for the case.

For example, the first expert who can set the “standard of care” in a medical negligence case gains the upper hand. By testifying to even the most elementary standards of documenting a medical file, the expert essentially becomes the voice of authority.

Good teachers anticipate questions that a student may have about the subject matter. In this mindset, they are always asking themselves, “If I were listening to this for the first time, what questions would I have?” They then make sure they answer those questions, no matter how basic or obvious they seem.

A good teacher also appreciates that different students have different learning styles. Some jurors are visual learners who need a great deal of graphic or demonstrative evidence to illustrate points. Some jurors are auditory learners who listen carefully to material, need a great of data and like to compare and contrast differing opinions. Some jurors are kinesthetic learners who like to use models, hold documents in their hands, and get a hands-on feel for the subjects they are learning about.

A good expert can appreciate these styles and create a mixture of methods to convey information. Some will walk jurors through a white board calculation of damages, some use PowerPoint to illustrate their process, and some will use models of the product in question. By using multiple media to convey the message, a good expert creates more interest in his or her testimony and easier access for the juror.

Tell a story

Good experts have the ability to tell a good story, breaking down complex subjects or concepts into simple, understandable language and organizing their material for optimal retention.

As an exercise, have your expert list the three to five major conclusions in their report. This method of organization is useful because it allows jurors to better organize their notes on the expert’s testimony and use that information in deliberations. This method also assists experts in organizing their own thoughts for cross-examination: no matter how vociferously they are attacked about their methods or conclusions, they can always come back to their major points.

A good storyteller also uses vocal variety to create interest in his or her message. Changes in pitch, intonation, emphasis, volume and pace of speaking create punctuation and accentuate the speaker’s content.

Most experts have learned how to make eye contact with jurors during their testimony. However, this can be overdone. Jurors have sometimes reported in post-trial interviews that the expert seemed to be pushing too hard by automatically turning to the jury after every question.

Jurors are already primed to be suspicious about the objectivity of an expert witness. However, if they perceive that there is some healthy resistance between both the attorney and the witness, they will have a harder time believing that the expert is just a “paid mouthpiece.”

To develop this resistance, the attorney and the witness can agree on areas where they disagree. Then, the witness can rein in the attorney and say, “No, I don’t think I would go that far. Here is what I think is a more accurate scenario.”

A second approach is for the attorney to step into opposing counsel’s shoes and “cross-examine” his own witness to preempt an anticipated attack. This allows the attorney to play the skeptic (something the jurors are already doing) and test the soundness and objectivity of the witness, and can sometimes leave opposing counsel with very little fodder for cross-examination. Both methods can be used to reinforce the independence of the attorney and the expert.

For jurors, credibility is highly subjective. By simplifying and clearly teaching a subject, the expert makes jurors the experts in deliberations, increasing the persuasiveness of their opinions.

Richard Gabriel is president of Decision Analysis, a trial consulting company with offices in Los Angeles, Chicago & San Francisco. He is co-author of “Jury Selection: Strategy & Science” published by Thomson-West.