therefore he is not criminally liable
that said, if I were him, I'd be a bit uneasy to visit the land of the free, Biden or no Biden. If you're waiting in arrivals, and they gently take you by the elbows and navigate through a side door, put a bag over your head and fast-forward, you find yourself in front of FISA court and declare guilty... I guess you have the right to protest all you want :(