Five Psychological Principles of Jury Persuasion

It is no accident that Thomas Mauet’s Fundamentals of Trial Techniques is the best regarded textbook for trial advocacy, at least among professors and adjunct professors who use a text at all. I kept a fair number of my law school textbooks, but the only one I’ve consulted more than once in 20 years of practice is Mauet’s Fundamentals.

In his chapter on trial strategy, Professor Mauet introduces us to some basic psychological principles which come into play when presenting evidence and argument to jurors. I’ll highlight five good ones here.

1.  Jurors are primarily affective, not cognitive, thinkers. This is probably a huge generalization, but a useful one. Mauet writes: “People have two significantly different decision-making styles. Most people are primarily affective, not cognitive, thinkers. Affective persons are emotional, creative, impulsive, symbol oriented, selective perceivers of information and base decisions largely on previously held attitudes about people and events.” (Id. at 376.)†

2.  Jurors use attitudes to filter information and reach decisions they believe are sensible and fair. We rely on attitudes, values and believes “to filter conflicting information. Our attitudes subconsciously filter information by accepting and remembering consistent information, by ignoring, minimizing, or rejecting inconsistent information, and by distorting inconsistent information to make it consistent with our attitudes.” (Id. at 377.)

3.  Jurors reach decisions quickly, base them on relatively little information, and then resist changing their minds. Just when you thought a jury trial was the perfect forum to resolve a technically complex dispute, such as a patent fight or generally accepted principles of accounting, it turns out that “[j]urors cannot absorb, understand, and retain most of the information they receive during a trial, particularly if most of that information comes through oral testimony. Sensory overload occurs quickly. To relieve the internal stress this problem causes, jurors reach decisions quickly by basing them on relatively little information that their attitudes have subconsciously filtered and received.” (Id. at 377.)

The key for a trial lawyer, then, is to identify the jurors’ “psychological anchors” and “state them in a short, attractive, memorable way that is consistent with jurors’ attitudes and beliefs, and incorporate them into each stage of the trial.” (Id. at 377-78.) For more on this, see my discussions of the Rules of the Road here. This is also consistent with the underpinnings of the Reptile strategy, discussed here.

Why do jurors resist changing their minds? Just as the rush to judgment is fueled by the desire to reduce internal stress caused by sensory overload, the steadfast adherence to their initial decision also helps reduce internal stress. “[I]nconsistent information causes cognitive dissonance–internal conflict and stress. Jurors subconsciously solve this problem by rejecting new information.” (Id. at 378.)

4.  Jury decision-making is influenced by the personality characteristics of individual jurors and how they will interact as a group. Mauet describes three types of jurors: leaders, followers and loners. Recognizing the leaders is key. “Opinion leaders usually have a higher education level and have positions of authority or expertise in their work. Leaders may be authoritarian personalities and often dominate jury discussions; the three most vocal jurors typically control more than 50 percent of the deliberation discussion. Particularly in longer trials, jurors form subgroups around opinion leaders.” (Id.)

Followers  . . . well, they follow the leaders. But loners are worth worrying about. “Loners . . . have no particular interest in either interacting or agreeing with other jurors. Loners who seem withdrawn because of recent traumatic experiences frequently become punitive jurors.” (Id.) Yikes!

5.  Jurors are influenced by medium variables. The message here is that jurors absorb what they see exponentially better than what they simply hear. Mauet writes, “When the medium is oral testimony, clear, simple common English with a smooth, confident delivery and reinforcing kinesic and paralinguistic cues significantly affect how jurors receive, accept, and retain the communication. . . Since communication is approximately 60 percent kinetic (appearance, gestures, body movement), 30 percent paralinguistic (voice inflection), and only 10 percent word content, trial lawyers must learn to read the kinesic and paralinguistic cues that jurors send during voir dire, witnesses send while testifying, and lawyers send throughout a trial.” (Id. at 380.)

Visual exhibits are hugely important. “Visual exhibits also have extraordinary retention properties. People retain about 85 percent of what they learn visually; retention of aural information is only about 10 percent. Hence, exhibits that pass the ‘billboard test’ — clear, immediate, and attractive — have an extraordinary impact on jurors.” (Id.)

With these psychological principles in mind, we can see why voir dire is so important, as is the packaging of messages, particularly anything that is complex or likely to trigger jurors’ long and closely held attitudes and beliefs. Good luck.

†All citations are to the Third Edition.