The effect of a suggestive interviewer on the performance of repeated eyewitness showup identifications

A study using a DON’T KNOW option.

Abstract

The present study examined whether providing a DON’T KNOW option reduce the influence of a suggestive interviewer on the performance of eyewitnesses in repeated showup identification procedures. Fifty-seven participants eye-witnessed a staged event in which a man took a wallet from an unattended bag; they were later interviewed twice. Each interview included two showup identification procedures: one with a suggestive interviewer and the other with a non-suggestive interviewer. In the showup identification procedure, the participants were shown pictures depicting a man and choose one of the three responses: YES, NO, or DON’T KNOW. The person who took the wallet was never in the picture shown, so a YES response was an incorrect identification (i.e. false alarm), and NO was a correct rejection. In the suggestive condition, the participants chose the YES significantly more often than NO and DON’T KNOW, while in the non-suggestive condition, NO and DON’T KNOW were significantly more frequent than YES. This indicates that providing a DON’T KNOW option does not reduce the influence of a suggestive interviewer. Furthermore, the participants in the suggestive condition tended to maintain their first identification response more often than the participants in the non-suggestive condition. The results were interpreted according to the conformity theory of memory.