[The effect of familiarity on eyewitness identification testimony: the relationship between accuracy and confidence]

In this study, we examined eyewitness identification involving a person who was slightly familiar to the witness. Although identification of a familiar person has been believed to be more accurate than that of a stranger, we expected that misidentification of a familiar distracter as the target would occur, and in such cases, the witness would be more confidence than when correctly rejecting the familiar person. A total of 102 participants were assigned to one of four conditions where familiarity with the distracter and the visibility of the target's photo were manipulated. First, they rated impressions of several photos in terms of personality traits to increase familiarity of some, then were presented with the target photo in either dark or bright condition. Finally, they were asked to identify the target in a two-photo lineup, where the critical trial included a familiar distracter. Results indicated that 66.7 per cent of subjects who saw the target photo in the dark condition misidentified the distracter as the target. At the same time, confidence for the choice (misidentification) was significantly higher than that of correct rejection. The findings were discussed from the forensic viewpoint.