Are you being lied to? This article: “How to Detect Lies” will turn you into a human lie detector.
For one horrible moment, it occurred to me that most of my mannerisms were listed under ‘Signs of Deception.’ I prefer to be vague while in the presence of questionable individuals, and apparently my body language is a reflection of this tactic.
Hmm.
79 Sparrows 
There’s a famous quote from ex-mayor of Philadelphia Frank Rizzo, who said something along the lines of “you can trust polygraph tests–if somebody fails a polygraph test, you know he lied” just before failing a polygraph test…
Overall, I think truth is too complicated for any lie detector…