When someone does not look you in the eye, starts doing something while talking to you (such as fumbling with a mug of coffey or whatnot) and gesticulates more than usual, he is almost always lying.
I disagree with that. When someone is trying to prove shit to someone else and the other one doesn't believe them, the first person would of course try to convince the second one that they didn't or did the thing in question, as to not seem like a dick or whatever the thing in question done makes them, aka a liar. It seems perfectly natural to me. In my opinion, those who give up on their stance that they did or did not do the action in question are more likely to be guilty.
By eager I mean the person comes forward and says they did not do a crime without being questioned or asked as to whether they did it or not. If someone is questioned as to a crime of course they will defend them selves by arguing against the accuser. Awesome quotes cannot explain themselves or it ruins the moment.