Induced suspicion of deception impairs eyewitnesses' memory of a suspect

Eyewitnesses to crimes sometimes perform cognitively demanding tasks while simultaneously observing a perpetrator. This division of attentional resources can cause them to remember the perpetrator less accurately. Pickel et al. (in press) showed that judging a target individual’s veracity impairs subsequent memory for his or her appearance and message. They argued that this result occurred because judging veracity is an attention-demanding task that is difficult to perform while simultaneously encoding the target’s information. The previous study also demonstrated that suspicion exaggerated the memory impairment effect, apparently by inducing suspicious witnesses to scrutinize the target more closely than non-suspicious witnesses. The goal of the present study was to replicate the findings that judging veracity impairs witnesses’ memory for the target’s appearance and message using a different video (i.e., a different target, crime scenario, and message) and that induced suspicion exaggerates this effect. In addition, I hypothesized that judging veracity also impairs witnesses’ performance on a lineup task and inflates confidence and ratings on other testimony-relevant judgments by giving witnesses the false sense that they have attended closely to the suspect’s physical appearance and message. I hypothesize that suspicion will exaggerate this effect. Results were found to be consistent with Pickel et al.’s (in press) previous findings. Witnesses who judged veracity performed more poorly on the lineup task than those who were not informed they would need to judge veracity, and witnesses who were made suspicious performed worse than those who judged veracity. Differences were discovered across the groups in relation to certainty ratings and other testimony-relevant judgments about the eyewitness experience.Department of Psychological ScienceThesis (M.A.