Groupdiscussion improves lie detection

Just because you get away with a lie to your wife does not mean you would be lucky in front of a group. Researchers have found that groups are consistently more accurate in distinguishing truths from lies than one individual is.

The group advantage in lie detection comes through the process of group discussion, not the product of a 'wisdom of crowds' effect, the results published in the journal Proceedings of the National Academy of Sciences (PNAS), showed.

"We find a consistent group advantage for detecting small 'white' lies as well as intentional, high-stakes lies told for personal gain," said one of the researchers Nicholas Epley, professor at the University of Chicago Booth School of Business in the US.

"This group advantage seems to come through the process of group discussion rather than statistical aggregation of individual opinions," Epley said. The modest accuracy rate of people who can detect deception is driven mostly by the tendency to detect truths, rather than lies. In the study, the researchers designed four experiments to test if individuals can do better to detect lies as a group.

The researchers found that group discussion could identify the most accurate person within a group which increases accuracy through a sorting mechanism. And secondly, group discussion could elicit observations about the target that provide information needed to make an accurate assessment.