There's no such thing as a "tell." For example, when people look up, fidget or stutter they might just be nervous, and not exactly lying. However, because we rely on the truth to make our culture go round, it might make our lives easier if we could just spot a liar out of the crowd.
As it turns out you can tell if people are telling the truth or not, but it takes some skill, time and knowledge.
In this edition of Two Guys on Your Head, Dr. Art Markman and Dr. Bob Duke talk about lying, and a new study that reveals a more accurate way to catch someone in a lie.