Lie Detection Performances and Beliefs in Different Groups of Professionals

Lie detection is part of various professionals’ mission, whether we think of the police, law enforcement, insurance, or education. Interestingly, we know little about their actual and self-reported lie detection performances. Only the police officers have received some attention in this regard, who showed similarly low lie detection performances and subjective overestimations in their performances as control participants. In this online study, we investigated the extent to which 65 police officers differed from (i) 82 lawyers, insurers, teachers (i.e., other professionals confronted with lies), and (ii) 220 non-professionals in their actual and subjective lie detection performances. All groups performed around chance level when deciding whether a person portrayed in the videos was lying or telling the truth. Groups also showed comparable confidence levels in their lie detection decisions. However, police officers were more realistic in their lie detection performances, while the other professionals and non-professionals overestimated their performances. We discuss these results in light of a recent professional training of police officers.