Deception detection: psychologists try to learn how to spot a liar

Science News, July 31, 2004 by Carrie Lock

Ekman and O'Sullivan speculate that if they could only study enough people, they might learn specific techniques that good lie detectors use. Then, it might be possible to deconstruct their skill and teach it to others, such as police officers, the researchers say.

Vrij, for instance, reports in the April Applied Cognitive Psychology that he has increased people's accuracy by a few percent by teaching them to make quick assessments of behaviors such as the frequency of hand movements. However, Levine speculates that even a bogus program can succeed by simply getting people to pay attention.

"Training may increase your hit rate a little bit in the long run, but you're still missing a lot," Levine says.

But because witnesses, hard facts, and physical evidence are often scarce, Ekman says, "it's worth training people to be as accurate as they can be."