Detecting Lies: Patterns and Deviation
Detecting lies can and has filled entire books. People are fascinated by catching people in dishonesty. In a survival aspect, this makes absolute sense. Figuring out those who want to deceive and being one step ahead keeps a person on top of the competition. However, there is a lot of oversimplification when it comes to detecting lies. Some of what is written on the internet is sensationalized. There are no catchall gestures that give people's dishonesty away. Instead, it is more about detecting patterns.
Condition to many situation from birth to present, people develop habits that they do inadvertently. Some people portray nervous gestures even when they tell the truth, so nervousness is not always a case of lying. The key is to look for gesture that are out of character. Some investigators will ask question that give them a feel for what the suspect's mannerism are. For example, the investigator may know that a suspect has a brother and ask him if he does while watching for nonverbal queues. Later, the investigator can spot body language that differentiates from previous behavior.
With that said, there are some behaviors that are associated with people who are uncomfortable. It should be pointed out that these behaviors do not mean the person is being dishonest, but mean that the person is uncomfortable. As former FBI agent Joe Navarro points out in his book What Every Body is Saying, these behaviors are an indicator that the question warrants further inquiry.
Navarro discusses that many people use self-touch in order to comfort themselves during times of stress. Touching one's own arm, for example, may be a sign of discomfort. Self-touches can be things like rubbing the forehead, ringing of the hands, and grabbing the throat. On the other hand, some people may cover their mouths as if they are physically trying to stop the words from coming out. This type of behavior can be considered as blocking. Blocking happens when the person in question places something between themselves and the person that is making them uncomfortable.
These are just some quick tips. As mentioned, there are many books that go further into behavior that indicates how to read body language appropriately. However, self-touches and blocking are good indicators that someone is uncomfortable and potentially be dishonest about something—and it may not be necessarily what the questioner thinks. With a keen eye and an analytic mind, anyone can spot these gestures and better detect deceit.