It's hard to define the concept of truth. But when it comes to spotting a liar, former federal agent JJ Newberry says what's key is understanding human behavior.
Newberry is known as a human lie detector - with a 90 percent success rate. He was an agent with the Bureau of Alcohol, Tobacco and Firearms for 27 years. He talks to The State We're In about how he’s learned to spot lies told by petty crooks and terrorists... and why he doesn't use his ability in his personal life.
This story was taken from the latest edition of The State We're In - Unmasked!