Truth or Lie: How to Tell

Is Herman Cain telling the truth or is he lying about the circumstances surrounding the sexual harassment claims made against him by women who worked under him while he oversaw the National Restaurant Association? As the questions multiply over the nature of the case, Cain is maintaining, for the most part, a poker face. But as detective shows and police know, liars always have their tells.
 In this slideshow, explore the different techniques for detecting a liar.