Nonverbal dominance versus verbal accuracy in lie detection: A plea to change police practice

Abstract

With the exclusion of some specific circumstances, police officers typically pay more attention to nonverbal behavior than verbal behavior when they attempt to detect deceit. One of the reasons for this is that they believe that suspects are less able to control their nonverbal than verbal behavior and, consequently, nonverbal cues to deception are more likely to leak through. The author states that this assumption is not necessarily valid; deception research has revealed that many verbal cues are more diagnostic cues to deceit than nonverbal cues. Paying attention to nonverbal cues results in being less accurate in truth/lie discrimination, particularly when only visual nonverbal cues are taken into account. Also, paying attention to visual nonverbal cues leads to a stronger lie bias (i.e., indicating that someone is lying). The author recommends a change in police practice and argues that for lie detection purposes it may be better to listen carefully to what suspects say. © 2008 International Association for Correctional and Forensic Psychology.