Lie Detection: What Works?

A reliable lie-detection method would be extremely useful in many situations but especially in forensic contexts. This review describes and evaluates the range of methods that have been studied. Humans are barely able to pick up lies on the basis of nonverbal cues; they do so more successfully with systematic methodologies that analyze verbal cues and with physiological and neuroscientific methods. However, the rates at which people are able to detect lies are still well below the legal standard of “beyond a reasonable doubt.” This means that the utmost caution must be exercised when such methods are employed. In investigations where independent evidence exists, there is emerging evidence that interviews based on a free account followed by the gradual introduction of the evidence by investigators can reveal inconsistencies in a guilty interviewee’s account. Automated machine-learning methods also hold some promise.