Nonverbal Dominance Versus Verbal Accuracy in Lie Detection

• Published date: 01 October 2008
• Date: 01 October 2008
• DOI: 10.1177/0093854808321530
• Author: Aldert Vrij
• Subject Matter: Articles

NONVERBAL DOMINANCE VERSUS VERBAL

ACCURACY IN LIE DETECTION

A Plea to Change Police Practice

ALDERT VRIJ

University of Portsmouth

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.

Keywords: lie detection; nonverbal behavior; deception; police interrogation

During police interviews, investigators need to know whether a suspect is lying when he

or she denies involvement in a crime. For this reason, police manuals about interview

and interrogation techniques often include sections about cues to deception. It strikes me

that in those sections typically more attention is paid to nonverbal cues to deception, partic-

ularly visual cues (i.e., gaze, movements, posture) than to verbal cues to deception (i.e., the

speech content) (see Vrij & Granhag, 2007, for a review of visual cues mentioned in police

manuals). This suggests that nonverbal cues are more diagnostic to deceit than speech content,

which is further emphasized with statements such as “as much as 70 percent of a message

communicated between persons occurs at the nonverbal level” (Inbau, Reid, Buckley, &

Jayne, 2001, p. 143). However, this statement is at odds with the deception literature. As

I discuss in this article, deception research has shown that many speech-related cues are

more diagnostic to deception than nonverbal cues. In addition, observers who just pay

attention to nonverbal cues are less accurate in discriminating between truths and lies than

those who take speech content into account. In addition, when observers just pay attention

to visual cues, they are more inclined to accuse someone, even truth tellers, of lying. I there-

fore argue in this article for a refocus of police practice, encouraging investigators to listen

more carefully to what suspects actually say.

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CRIMINAL JUSTICE AND BEHAVIOR, Vol. 35 No. 10,October 2008 1323-1336

DOI: 10.1177/0093854808321530

© 2008 International Association for Correctional and Forensic Psychology

AUTHOR’S NOTE:This project was sponsored by a grant from the Economic and Social Research Council

(RES-000-23-0292). Correspondence concerning this article should be addressed to Aldert Vrij, University of

Portsmouth, Psychology Department, King Henry Building, King Henry 1 Street, Portsmouth, PO1 2DY, United

Kingdom; e-mail: aldert.vrij@port.ac.uk.