Unusual Body Language

• The most important thing to look for in lying is a change from the norm. People have a way they tell stories and relate to others when they are acting normal and not self-conscious. When someone lies, he won't look as natural. If you know someone well, your instincts may tell you that something is different when he lies.
  
  

Awkwardness

• Liars often become stiffer and more compact when they lie. Rather than making normal, expansive gestures with arms and legs, they will hold their arms fairly still and close to their body. Their movements will appear forced and self-conscious.
  A liar will also make irregular eye contact. He may avoid it altogether, or stare fixedly at you as if trying to prove he is telling the truth. He may touch his head, mouth and ears frequently when lying, but is less likely to touch his chest.
  
  

Disconnect Between Statement and Expression

• Another good body language cue to look for is an inconsistency between a statement and a facial expression. Normally, the two occur very naturally together. When someone lies, she may not convey the appropriate facial expression. On the other hand, she may do it out of sync with the statement in a way that looks forced. For example, if someone says, "it's so nice to see you" with a flat expression, suddenly smiles for a bit too long, then goes back to the flat expression, she is probably lying. This is often called a "business smile."
  
  

Overacting

• Sometimes, people overact when lying. This sort of "actor" will not necessarily tense up and contract. He may instead become dramatic, expressing his story with sweeping movements to try to get you to believe it. He may nod his head repeatedly to try to get you to agree, or stroll back and forth to diffuse the tension he feels when lying.
  
  

Other Hints

• Although all of these body language cues can be signs of lying, many of them can indicate other things as well. If someone is uncomfortable in a situation, for example, she can become stiff, touch her mouth and have awkward facial expressions even if she isn't lying. On the other hand, a good liar may have fairly natural body language when he lies. Body language provides some good clues about lying, but it does not tell the whole story. You need to look at speech patterns, inconsistencies in the story, and other pieces of evidence to really determine whether someone is lying.