One can argue however that you need to be saying something in order to be lying.
So logically he has never told a lie because he's never said anything that has substance.
Aren't you watching Lie To Me? Everything is a tell!
Seriously, look into lie detection. It's pretty interesting. I've been researching it for years- there was a period on ATS where a lot of people
were interested in it.
I'd be amused to see someone either than the lady on O'Reilly dedicate time to analyze political people's motions and micro facial expressions.