The following are signs you should look for when attempting to spot a liar:
Body Language: Liars usually hide their palms, don’t sit straight while telling a lie, avoid eye contact at the time of the lie and generally use negative evaluation gestures if they feel bad while lying.
Eye Accessing Cues Mismatch: According to NLP the direction that the eye is currently looking reflects the function that is currently happening in the brain. For example, looking to the upper left means that you are constructing an image in your mind, while looking at the upper right means that you are recalling an image. So how can that be of use? Well, think about it, if someone is looking to the upper left when telling asked about something, he's probably constructing an image of the lie he's about to tell. This is just one sign that he might be lying.
Inconsistency in Telling the Story: If you have the chance to open the same subject with him at different times or at different places, his story will most likely change each time he discusses it. He will forget a word, add something completely new, or remove something that he had previously mentioned. Regardless of the type of inconsistency, it show's that he is lying.
Feeling Anxious: Almost anyone who lies feels anxious, although this may happen with varying degrees depending on how professional the liar is. One of your tasks should be to try to spot his state of anxiety. Try to talk as much as you can about the subject in order to keep him anxious. Check out anxiety body language in order to be able to detect anxiety.
Avoiding the Subject: A person who wants to hide something will usually try to avoid bringing the subject into conversation or talking about anything that is related to it. Try to talk about anything related to the situation without addressing the situation directly and see if he tries to jump to another topic.
Lack of Assertiveness: Unless that person is a special agent who is professionally trained to lie, he will usually lack assertiveness while lying. His tone of voice will be lower and he will appear to be less confident about it.
Speaking Slowly: When lying, the person will usually be making up events as he goes along and this will result in a slower rate of talking or even stopping several times to think about what he's about to say.
It's very important to know that there are many other variables involved in this process, and so I suggest that you use these methods for decision support and not for sole judgment on others. For example, if you suspect that someone is lying, you should then start to see if any of these signs are present. Of course the more signs you find the more likely that person is lying.
Read More at InfoTank on Body Language:
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