[Gil4]

Mr McGraw, you have a perfect right to defend yourself, but your defense attorney will thank you if you don’t make remarks like that to the press first.

He wasn't defending himself. The idiot protester was being marched out of the building. The idiot Trump supporter (not an indictment of Trump - that's just what the guy was) sucker-punched him (or sucker-elbowed him, to be more accurate.) The protester was no threat - security was leading him out, and he was leaving.

According to this link, McGraw was later charged with assault and battery and disorderly conduct. That seems appropriate to me.

[Slings and Arrows]

I should have been more clear - I meant in the case that the man McGraw assaulted came looking for revenge. I concur with your description of the initial incident.