Lie-Detection Biases among Male Police Interrogators,Prisoners,and Laypersons

Beliefs of 28 male police interrogators, 30 male prisoners, and 30 male laypersons about their skill in detecting lies and truths told by others, and in telling lies and truths convincingly themselves, were compared. As predicted, police interrogators overestimated their lie-detection skills. In fact, they were affected by stereotypical beliefs about verbal and nonverbal cues to deception. Prisoners were similarly affected by stereotypical misconceptions about deceptive behaviors but were able to identify that lying is related to pupil dilation. They assessed their lie-detection skill as similar to that of laypersons, but less than that of police interrogators. In contrast to interrogators, prisoners tended to rate lower their lie-telling skill than did the other groups. Results were explained in terms of anchoring and self-assessment bias. Practical aspects of the results for criminal interrogation were discussed.