When people lie they often take a particular stance or a means of expression. This seems to be an inner betrayal of their deception.
Just look at President Clinton waving and wagging that finger again. You know, "...I never had sex with that woman, Monica Lewinsky..." was also accompanied by finger wagging.
Anyone who has the video tapes of both should post them. It will prove interesting.
Today's video: http://www.youtube.com/watch?v=3UwJabtvSUQ
It's his own peculiar "tell".
[He definitely should *not* take up poker playing]....:)
http://en.wikipedia.org/wiki/Tell_%28poker%29