Cry me a river: identifying the behavioral consequences of extremely high-stakes interpersonal deception

Deception evolved as a fundamental aspect of human social interaction. Numerous studies have examined behavioral cues to deception, but most have involved inconsequential lies and unmotivated liars in a laboratory context. We conducted the most comprehensive study to date of the behavioral consequences of extremely high-stakes, real-life deception--relative to comparable real-life sincere displays--via 3 communication channels: speech, body language, and emotional facial expressions. Televised footage of a large international sample of individuals (N = 78) emotionally pleading to the public for the return of a missing relative was meticulously coded frame-by-frame (30 frames/s for a total of 74,731 frames). About half of the pleaders eventually were convicted of killing the missing person on the basis of overwhelming evidence. Failed attempts to simulate sadness and leakage of happiness revealed deceptive pleaders' covert emotions. Liars used fewer words but more tentative words than truth-tellers, likely relating to increased cognitive load and psychological distancing. Further, each of these cues explained unique variance in predicting pleader sincerity.