Expert Witness Dispute Resolution

It is common experience that jurors will often set aside expert testimony. Part of it, of course, is a "hired gun" effect that in some cases leads jurors to distrust experts based on the knowledge that they've been paid for their opinions by one side or the other. But over time, I've come to believe that is not the dominant reason jurors have for avoiding reliance on experts. Instead, there is a more basic reason at work: Jurors don't use experts because they're not convinced they need experts. They think they know the general idea well enough already. Why listen to a product safety expert if I think product dangers are obvious based on common sense? Why listen to a construction expert if I have a brother-in-law who works in construction?

This overconfidence and preference for personal knowledge has a social science name: the illusion of explanatory depth. It's a cognitive bias that occurs when people believe they understand a concept more fully and more specifically than they actually do. The way it works is this: Once we're able to appreciate or articulate something at a very general or abstract level, we come to believe that we understand the specifics and the mechanics of it at a concrete level as well. But, we don't. As one of the most comprehensive recent studies of the phenomenon (Alter, Oppenheimer & Zemla, 2010) has noted, this perceived general understanding isn't something we can trust. "Although folk wisdom suggests that people often fail to see the forest for the trees," the authors note, "sometimes the greater concern is that people fail to see the trees for the forest." That has an immediate relevance to jurors' and other fact finder's understanding of expert testimony. Jurors can fall victim to overconfidence in understanding, and the experts themselves can unwittingly promote that illusion. The main goal is to avoid abstract explanations and be concrete instead. In order to practice what I preach, I mean to concretely explain in this post what I mean by "be concrete." 

Missing the Trees for the Forest: The Illusion of Explanatory Depth

Cognitive science seeks to understand how our patterns of thinking explain our actions and decisions. The research I'm looking at in this post (Alter, Oppenheimer & Zemla, 2010) addresses the question of "why people believe that they understand far more about natural processes, their abilities, other people, and future events than they actually do." The illusion of explanatory depth is a common way we overestimate personal knowledge. The authors use the following example: 

Many people know vaguely that an earthquake occurs because two geologic plates collide and move relative to one another"...."but they know little about the mechanism that initially produces these collisions. Nonetheless, people believe they understand these concepts quite deeply and are surprised by the shallowness of their own explanations when prompted to describe the concepts thoroughly.

In other words, possessing only the most general outline of something, we think that we can translate that outline to the specifics, and we can't. That can cause problems in applying expert opinion testimony. If we think we understand the phenomenon better than we actually do, we're more likely to rely on our own knowledge instead of expert opinions. 

But what determines whether we fall into this illusion or not? What the researchers found was that it boils down to whether we are using an abstract or a concrete route to understanding. Referring to this as a "construal level," they explain that "people construe or represent the environment along a continuum from abstractly to concretely." In looking at how a simple pen works, for example, you might have a global understanding (I move it across a paper and ink appears), or a concrete understanding (there is a ball in a socket between the paper and the ink, and that ball serves to separate the ink from the air and to transfer that ink in small amounts to the paper as it rolls).

By measuring and inducing this broad or detailed understanding of situations like the earthquake or the pen, the researchers looked at whether they could cause and prevent this illusion. Through a series of six studies, they found that individuals do commonly experience an illusion of explanatory depth, and when they approach information abstractly (either naturally or after being induced to do so by the researchers), they are more likely to experience this feeling of having greater understanding than they actually have. Across the six studies, they found what minimized this illusion was concrete construals - the action of thinking about phenomena in tangible and physical terms, rather than broad and global abstractions. "Our findings suggest that whenever people instinctively adopt an abstract construal style, they might erroneously conclude that they understand fine-grained, concrete concepts more deeply than they actually do." 

That observation provides a useful addition to a good expert's toolbox. By now, it is common advice to pare back on the jargon and to adopt a teaching mindset. But taking it even further, experts should try first to convey a concrete understanding by letting the example lead and the explanation follow. Instead of doing that, however, experts too often will explain broadly, dipping down to a concrete level only to provide some illustrations. It is a trick of language: As we move up the ladder of abstraction, focusing on forests rather than trees, we feel that we are explaining more, but in practical terms, we are explaining less.

Concretely, here are a few things that experts and those who hire them can do to stay on the concrete side.     

1. Focus on How and Not Simply on Why

Formally, the law puts the focus in expert testimony on the expert's conclusions and the reasons for those conclusions. That makes sense given the expert's role, but from a communication perspective, it lodges the expert firmly in the "abstract" department when it comes to the level of construal, or understanding, that jurors and other fact finders are being asked to use. In the Alter, Oppenheimer and Zemla (2010) study, the researchers provided a simple trigger that experts and other legal persuaders can use. When they wanted to induce an abstract style of thinking, they would ask "why," but when they wanted to induce a concrete approach, they would ask "how." Experts can follow the same pattern. Instead of focusing primarily on reasons and conclusions, immediately engage the fact finders by focusing on how.

For example, in one of our more complex cases, we had a damages expert on the stand for several days who had to provide a detailed account of economic losses. Feeling the rather substantial risk of losing the jurors in the first twenty minutes, we focused the early parts of that testimony on the expert's process. Like a mathematics story problem, the expert walked the jury in a step-by-step fashion through the challenges he faced and the solutions he applied, so that jurors had the chance to see the concrete how before getting into the greater abstractions of what and why.

2. Start With What You Can Show, then Work Back to What You Can Tell

Last week, Anderson Cooper featured restaurant industry expert witness, Howard Cannon, on his show to talk about the sources of food poisoning we face when dining out. If you look at the clip, you'll see that the same techniques they chose to make for interesting television also make for effective testimony. Instead of talking abstractly about things that we can't see (bacteria, kitchen conditions, etc.), Cannon led with a number of concrete illustrations of the specific and visual scenarios that can cause illness or even death from food poisoning. 

That approach can be replicated in court. In one of our cases, for example, our witness needed to explain to jurors the concept of "microbial imbalance" which occurs when the act of wiping out some good microbes causes other harmful microbes to flourish. Of course, it was all explainable in the abstract, using data and tables, but what jurors remembered is the animations, the analogies (if you kill the wolves, then there are too many deer), and a demonstration in which the expert was allowed to step up to the jurors and show them various petri dishes containing microbial communities glowing under a black light. Instead of focusing first on the "main testimony" and then, almost as an after thought, thinking of ways that you might use graphics to illustrate it, start with the graphics that engage the jurors immediately on a concrete level. 

3. Vet Your Expert's Teaching Ability As Much As You Vet Their Expertise

Of course, getting fact finders to the concrete level requires some skill on the expert's part, and you should look into that skill when hiring your own experts and assessing the experts on the other side. There are companies that will provide comprehensive profiles for your expert (e.g., "Expert Witness Profiler"), and while those reports will generally include the most saliant indications of experience and credibility that the law sees (e.g., teaching, publications, past testimony, etc.), they often leave out the quality that I'd consider most important: Can this expert effectively communicate their conclusions to an audience of laypeople? Beyond qualification, can they truly teach the unfamilar and the abstract? Or, viewed in the light of this research, can they encourage jurors to set aside their illusion of explanatory depth long enough that they actually rely on the expert's opinions instead of their own folk wisdom on the subject? To assess these questions, there is no substitute for your own experience with a witness or your own conversations with those who've had experience with the witness. 

There is one final point on the illusion of explanatory depth, and it bears on case settlement. "Our research suggests" the psychologists explain, "that negotiators who adopt an abstract construal style may overestimate the prospects of resolving an intractable disagreement as they fail to fully consider the issues in concrete detail." In other words, the trial teams themselves may fall victim to this illusion if their own thoughts of case risks or case settlement conditions are allowed to drift into the abstract, instead of being anchored in the concrete. That is another benefit of a mock trial exercise: It forces you to move from global thinking about both your case and their case, and to move toward a more concrete understanding of what each side will be trying to say and do in trial. It forces you out of the forest and into the trees.