Police officers' lie detection accuracy: interrogating freely versus observing video

The study investigated experienced police officers’ (N = 30) lie detection accuracy. Each police officer conducted an interrogation of a college student acting as a suspect either guilty or innocent of a mock crime and made a veracity judgment of the suspect. The police officers had the opportunity to conduct the interrogation in the manner of their own choice. The lie detection accuracy of these police officers was compared to that of police officers judging videotaped versions of the interrogations. The police officers failed to detect deception better than chance. There was no difference in accuracy between police officers interrogating live and observing video. The interrogators reported to rely on verbal content more when interrogating than when watching video. It seems as though police officers have a difficult time detecting deception not only in passive contexts but also in active ones.