Optimizing the selection of fillers in police lineups

Eyewitness misidentifications have contributed to many wrongful convictions later overturned by DNA evidence. In response, many useful reforms have been introduced to protect the innocent. However, some police practices designed to protect the innocent also protect the guilty. We investigated a method for selecting fillers in a police lineup that protects the innocent while also making it easier to identify guilty suspects. Intuitively, fair lineups are created by choosing fillers who are similar in appearance to the suspect. However, we found that choosing fillers who match the description of the perpetrator but who are otherwise dissimilar to the suspect's appearance yield fair lineups and enhance eyewitness identification performance. It does so by imperiling the guilty while protecting the innocent.