An asset for any police officer is the ability to know when someone is lying. Sometimes lies can be revealed when a suspect contradicts himself or provides implausible explanations. But one of the best ways to detect lies are nonverbal cues that reveal the stress accompanying deception. Many aspects of our bodily functions and other physical behaviors are beyond our control. We cannot keep out bodies from perspiring or slow down our pulse rate during physical exertion or moments of stress. It is because most suspects cannot control these actions that these cues are such effective indicators of deception.The physical behavioral indicators described below are just some of many. They are highly effective in helping officers detect criminal activity and protect themselves from danger. They go beyond the simple nervousness one might experience in a 'normal' encounter with an officer, such as a traffic violation.
NO-LOOK MANEUVER: This signal occurs before the encounter ever takes place. At an intersection, for example, a motorist absolutely refuses to look towards the officer. An offender who has something to hide will resort to exaggerated effort to avoid direct eye contact with a police officer in a chance encounter.RESTLESSNESS: A high level of stress often causes a person to be very fidgety, shifting positions frequently, pacing, crossing and uncrossing arms. A stressed person may also try to move away, attempting to increase their comfort zone in order to reduce the anxiety.
FALSE FATIGUE: Signs of fatigue may actually be efforts by the body to relieve stress. Frequent yawning and sighing are good stress relievers in these circumstances.