answer:Here is how you can definitely catch a liar: (1) Get a politician. Er, that’s it. (Seriously, there is no reliable way to tell whether or not a person is lying. Sodium pentathol, micro-expressions, and the polygraph machine have all been debunked. There are a few general cues—for example, we know that people are more likely to make direct, sustained eye contact when lying—but they are far from reliable, and all can be manipulated by a skilled liar.)