How to tell if somebody is lying: - Barking up the wrong tree

How to tell if somebody is lying: - Barking up the wrong tree: "'Lying taxes the mind,' Wiseman explains. 'It involves thinking about what is plausible. People tend to repeat phrases, give shorter answers, and hesitate more. They will try to distance themselves from the lie, so use far more impersonal language. Liars often reduce the number of times that they say words like 'I', 'me', and 'mine'. To detect deception, look for aural signs associated with having to think hard.'

According to the Canadian Journal of Police and Security Services, another side-effect of lying that forensic interrogators will look for is the avoidance of verbal contractions - using 'I am' instead of 'I'm' and so on. Nature reported another study by Ioannis Pavlidis of Honeywell Laboratories in Minnesota. He established that many people blush when they are telling a lie - a subtle, but detectable, phenomenon. Pavlidis has developed a thermal-imaging technique that he says detects deceit by recording thermal patterns in people's faces. He's shown this technique to have an accuracy rate comparable to that of polygraph examination by experts, and says his method has vast potential for application in rapid or remote security screening (at airports and border crossings, for example), without the need for skilled staff or physical contact."