When Expert Witnesses Are the Problem

What should we do when an expert witness provides incorrect or biased information in court? When people review exonerations of falsely convicted innocent people, bad forensic evidence and misleading expert testimony have often played a role (Bonventre, 2020; Garrett & Neufeld, 2009). There have been a few high-profile cases recently – times when the experts may have led courts and juries astray (you can read about some cases in this NY Times article).

Problems With Forensic Evidence and Expert Witnesses

Sometimes the science underlying forensic evidence is bad. Consider, for example, using bite marks to identify who attacked someone. Many people have been convicted of assault based on bite mark evidence – claims that a person’s teeth must match a specific bite mark. But it turns out that bite marks can’t be used to uniquely identify a person. People have correctly lost confidence using bite marks to identify perpetrators (Zalman & Windell, 2019).

In other cases, the underlying science is strong but is misrepresented by an expert witness. Good science can be misused. I will focus on the misuse of attention research, particularly concerning inattentional blindness.

The Clear Science of Inattentional Blindness

Inattentional blindness is a well-documented phenomenon. In a complex environment, people may become focused on a single thing. When focused, they may fail to see something unusual and unexpected.

The classic example was created by Ulric Neisser and his students. They had two sets of basketball players, each passing a basketball – one in white shirts and the other in black shirts. You are asked to count the number of passes the players in white make. This gets you focused on one thing.

Then something unusual happens. In the original work, a woman walked through the game carrying an umbrella. If you’re counting passes, you are likely to miss the umbrella woman. But critically, people who aren’t counting passes see the woman. If you rewatch the film without counting, you’ll see her too and be surprised that you could have missed her.

There are many demonstrations and investigations of this. Simons and Chabris (1999) showed that people could miss a gorilla. In our research, we’ve shown that people talking on a cell phone can fail to see a unicycling clown (Hyman et al., 2010) or money hanging on a tree (Hyman et al., 2014). When people aren’t focused on their phones, they’re more likely to see the clown and the money.

Inattentional blindness is a documented effect. People get focused. They fail to see something unrelated to their focused attention. And the unusual thing is seen by people who aren’t focused.

The Misrepresentation of a Real Effect

Now let’s turn to the misrepresentation of this by expert witnesses. Let me introduce you to William Lewinski and his colleagues at the Force Science Institute. Lewinski has been the focus of several news stories – most of these have been about police officers killing unarmed people. In the NY Times, it was noted that he trains police to shoot first and quickly. He then defends that action as an expert witness.

Lewinski has misrepresented inattentional blindness to defend police officers who shoot unarmed people. He claims that police officers get focused on one thing during an event. He has argued that when officers shoot someone, they will become completely focused and experience inattentional blindness.

But they don’t miss something unrelated. Instead, he argued that they miss critical features of the person they are shooting – such as that they are not a threat, or that they don’t have a weapon, or that the person being shot is a child holding a toy gun (see this in an article in the San Francisco Chronicle).

This isn’t inattentional blindness. People experiencing inattentional blindness fail to become aware of things outside the focus of their attention. Lewinski has argued that people fail to notice things about the person they are focused on. Using inattentional blindness to argue that police are unaware that the person they are shooting is not a threat is a misrepresentation of what inattentional blindness is.

Evaluations of the Misrepresented Claims

A few years ago, I wrote about which aspects of research of inattentional blindness are ready to use in legal settings (Hyman, 2016). When I got to Lewinski’s claims, my conclusion was straightforward – “Simply stated, Lewinski’s conclusions on the role of inattentional blindness in police shootings and memory cannot be justified by the existing scientific data.”

Attention Essential Reads

Why the Limits of Language Are the Limits of the World

Drop It Like a Squat: Exercise Breaks Can Enhance Attention

More recently, Alia Wulff and I have completed an experimental investigation of whether people who are focused on one thing experience inattentional blindness for things outside their focus of attention and for the thing on which they are focused. Inattentional blindness was documented again for things outside the focus of attention.

But critically, we found that people who were focused remembered the focus of attention better than people who weren’t focused on that aspect. This is the opposite of what Lewinski has claimed should happen. We noted that inattentional blindness does not decrease awareness and memory for the focus of attention.

An Ongoing Problem

I had hoped that following my earlier work, the people at the Force Science Institute would stop using inattentional blindness inappropriately. But in their evaluations of news stories at the Force Science Institute website, they continue to misrepresent inattentional blindness. The people associated with the Force Science Institute have incorrectly claimed that inattentional blindness could explain a wide variety of cases in which police officers have shot unarmed people.

I wrote this piece with a simple goal. I would like to see them stop misrepresenting science. Inattentional blindness is a real phenomenon. But William Lewinski and others associated with the Force Science Institute have misrepresented this line of research. I ask them to please stop doing this. And I am working to make sure that any use of this line of research in legal settings is done appropriately.