Familiarity-Induced Biases

The Other factor is perhaps the most subtle, as it per- tains to familiarity-induced biases. Research shows that people often remember a face but not the circumstances in which they saw that face. In one study, for example, participants witnessed a staged crime and then looked through mug shots. A few days later, they were asked to view a lineup. The result was startling: Participants were just as likely to identify an innocent person whose picture was in the mug shots as they were to pick the actual criminal! Many different stud- ies have shown that witnesses will often identify from a lineup someone they had seen in another context, includ- ing innocent bystanders who also happened to be at the crime scene .