It's a common trait with habitual liars. Their first line of defense to giggle, laugh or smile. This is often done in a weak attempt to distract the opponent and more importantly it gives the liar time to think of something cleaver all while they're being beaten like a drum. Big league failure for Biden.
It makes me livid.
Watching this debate was the first time I’ve really suffered that fool for more than 5 minutes.
He is intolerable.