Do people tend to avert their gaze when they lie?
One of the biggest myths about body language is the belief that eye contact, or lack of it, exposes a liar, says Michael Wheeler, a professor at Harvard Business School and an expert on negotiation tactics.
Even when presented with psychological evidence to the contrary, many of us still suspect that liars out themselves by averting their eyes. Says Wheeler, "It's very hard to surrender the belief that eye contact is a test of character."
Far more reliable than eye contact is tone of voice. With the exception of sociopaths, who are expert liars, most people sound tense, their voices highly pitched, when they fib.
However, don't confuse voice tone with verbal fumbling. People who are telling the truth tend to stumble over their words and have more imperfections in their speech. That comes from spontaneity, not nervous deceit. Studies show that liars tell less compelling accounts with fewer gestures than those who are telling the truth.