Technosavant
Member
Probably nothing. Could you see the legal problems of a Champion Marksman in a self defense shooting.
No worse than you'd find for the intended victim in any "mugger gets rear handed to him by martial arts expert" story. In the vast majority of jurisdictions the authorities would likely chuckle and chalk it up to an EXTREMELY major failure of the victim selection process.
I'd probably expect him to carry a J frame when concealment is difficult, and a x25 variant when it isn't. Maybe somebody can ask the next time they come across him. I'd imagine he might be around the NRA convention.