Eyewitness Identification Has 50% Error Rate? How We Throw People in Prison Based on False ID
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“We see what we want to see,” my grandmother used to say. This insight visited me recently after I ran across the mall chasing a woman I thought was my cousin. It wasn’t, as it turned out, but I didn’t realize that until after I had puffed up behind her, bopped her amiably on the shoulder and cried out, “Boo!”
How was it possible, I thought in retrospective embarrassment, to so wrongly misidentify someone I know so well? Empirically my experience was all too common. I’d been thinking about my cousin a few moments before and saw the woman through the lens of those thoughts. We often project our life’s associations onto the faces of strangers. Constantly—if mostly unconsciously—we familiarize them with learned stereotypes. If we are wise, we learn to take caution with our assumptions. We recognize this innate fallibility, and most of the time it doesn’t matter very much.
Oddly enough, however, we reverse that supposition in the one context where fallibility matters most: in criminal cases, eyewitness testimony is viewed as the ne plus ultra for the prosecution, despite a century’s worth of psychological and sociological studies revealing that, from Sacco and Vanzetti to Troy Davis, witnesses misperceive a startling percentage of the time. “Human beings are not very good at identifying people they saw only once for a relatively short period of time,” writes Cornell law professor Michael Dorf. “The studies reveal error rates of as high as fifty percent—a frightening statistic given that many convictions may be based largely or solely on such testimony. These studies show further that the ability to identify a stranger is diminished by stress (and what crime situation is not intensely stressful?), that cross-racial identifications are especially unreliable, and that contrary to what one might think, those witnesses who claim to be ‘certain’ of their identifications are no better at it than everyone else, just more confident.”
The costs of this phenomenon are perhaps best revealed in data compiled by the Innocence Project, which has concluded that out of 281 postconviction exonerations secured through DNA in the United States, eyewitness misidentification “was a factor in 75 percent…making it the leading cause of these wrongful convictions.” Luckily, there are substantiated ways to guard against such error. Experts have cited two main types of variables that can adversely affect eyewitness identification: “estimator variables,” the hardest to control for, which include things like the degree of lighting, distance or speed within a given crime scene, as well as the level of trauma to the witness; and “system variables,” defined as “those that the criminal justice system can and should control,” which include law enforcement tools like lineups and photo arrays. A number of reforms involving the latter have the proven capacity to boost the accuracy of witness IDs. These include “blind administration,” where an officer conducting a lineup is not aware of who the suspect is (and thus not capable of revealing his or her identity via gestures, vocal inflections or body language); “non-suggestive” lineups, made up of people who generally resemble a witness’s description, so that the suspect does not stand out; allowing witnesses to sign a statement indicating their level of confidence in their choice; and presenting members of a lineup sequentially rather than simultaneously (to mitigate the pressure to choose any kind of close-looking one when we are presented with a bunch of faces at once). Such remedial safeguards have so reduced the error rate—and so indisputably—that a number of local jurisdictions and eleven states thus far have adopted some or all of them as standard operating procedure.