Source of the following article Persuasive Litigator.

By Dr. Ken Broda-Bahm: 

Reg human expert img

The expert takes the stand, his credentials proudly displayed to the jury as he launches into the dissertation of his testimony. Amid the complex chains of reasoning, the opaque references to other testimony, and the indecipherable jargon, it seems that he is giving an opinion on the case. But the impression the jury gets is “learned” and “detailed” but, unfortunately, not “helpful.” And when it comes time to deliberate, they’re likely to fall back on their own intuitions and experiences instead of using that expert’s opinion. That is what happens when the expert succeeds at his own goal of providing a sound opinion, but fails at the more important goal of good and clear communication. 

A recent article appears in Scientific American: “Why Can’t Scientists Talk Like Regular Humans?” Author Katherine Wu, a Harvard graduate student and director of ‘Science in the News,’ an organization devoted to better communication of science, describes her own experience in being trained to communicate mostly with other scientists in her field, and to dissociate that from the broader public. “The minute I started thinking of the general public as ‘other,'” she writes, “I compromised my ability to be an effective communicator.” The act of becoming an expert separates you from everyone else. She continues, “Suddenly, I was wheeling and dealing in the private, elite trade of science, far from prying eyes. I felt as though I had been inducted into a secret society: I had transitioned out of the common masses and joined the ranks of the fabled Jedi.” She blames current gaps in the public’s understanding of key scientific concepts, like climate change and genetically modified foods, in part on scientists’ separation from the general public. For expert witnesses, that separation is ultimately destructive to the witness’s goal of communicating in a helpful manner. Wu includes her own list of implications for scientists in the public square, and in this post, I include my own list for those in the witness box. 

Remember that Science and Effective Communication of Science Are Two Different Things 

The expert has two hats: the ‘expert’ and ‘the communicator.’ And when she is on the stand in particular, it is that second hat that needs to be the taller and more spectacular hat. For experts who spend most of their time (properly) on methods and conclusions, it can still be a mistake to treat the communication role as just a simple matter of looking at the jury and dialing down the jargon a bit. Effective teaching of science and other expert subject matters is its own skill, and skill on the subject matter does not mean skill as a communicator. Both need to be worked on. 

This is a particularly important thing to remember since scientists are selected, trained, and rewarded based on their ability to talk to other scientists. Visit an academic conference sometime if you want to be reminded of just how distinct and insular that communication can be. And the higher the expert gets in her field, the smaller the group of ‘peers’ she has and the more specialized (and inaccessible) those conversations become. For an expert witness, you need the right mix of both. And the expert needs to remember that understanding is not the inevitable result. Wu quotes George Bernard Shaw, “The single biggest problem in communication is the illusion that it has taken place.” 

Get Off the Pedestal 

An implied hierarchy says to the expert, “You are better than those sitting in the jury box,” and the court process reinforces that hierarchy. After all, at least until the end of the case, the expert is the only one who gets to offer opinions. But according to Wu, some humility is in order for scientists. “For each and every one of us,” she says, “there is at least one field that is unknown, a field in which someone else considers us the general public.” That includes the jury. They might look like an undifferentiated collection of humans, but the more you know about them as individuals, the more you learn about their sometimes surprising interests and areas of expertise. As an expert, it is not that you’re superior. It is that you are just useful in this one particular context.  

Focus on Method, not Knowledge

Whether a jury, a judge, or an arbitrator, the fact finder who is the audience for your testimony does not want to be in the passive role of just hearing your opinion and accepting or rejecting it. Instead, they want to be in the active role of at least feeling like they arrived at their own conclusion. So looking at it from a fact finder’s eye view, it is not just what you know, it is how you got there. For that reason, the message cannot be just the credentials-based view that reads, “Trust me, I’m an expert.” Instead, the message needs a strong component of “Show your work,” so that, in effect, you are saying, “Let’s work our way to this conclusion together.” Method isn’t infallible, but the right method is better than the alternatives, and more importantly, it provides fact finders with the assurance that they are exercising their own independent judgment and and not just being led along by a fancy expert. 

But Don’t Use Good Communication as an Excuse for Inaccuracy

Adapting should not mean distorting. “When I earn my Ph.D.,” Wu explains, “I might be able to say, ‘We think we may have come across something that explains a minuscule portion of a complex pathway that might be correlated with a slightly elevated risk of contracting this disease—but our findings are pretty specific to this one population studied at this point in time under these conditions.’ Meanwhile, media headlines say, ‘Lemons cure cancer!'” Of course, there is a point at which caveats that sound normal in a scientific context will be misread by the average audience. For example, listeners might reduce Wu’s first statement on her research to ‘We don’t really know much of anything’. Be honest and don’t over claim, but focus on what you do know.  


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