As several people have pointed out, there ain’t no such thing as an accidental shooting. If you shoot someone, the best you can hope for is a verdict of negligence. The first law of firearms is: Yes, the gun is loaded.1 You keep your finger off the trigger, you don’t point at your friends, you don’t point at things behind which you have friends.
If you give your hunting buddy a birdshot facial, you broke some of those rules.
He should be forced to do embarrassing public service announcements about the topic.
Maybe dressed up in a fairy suit. “Hi there. I’m Dick Cheney, and I’m dressed up as one of the Ammo Fairies to make a point. You know, the Ammo Fairies? They go around putting ammunition in unloaded guns when no one is looking. That means you should always assume a gun is loaded! Some folks may think the Ammo Fairies don’t really exist, but people who believe in them live longer than people who don’t! Ho, ho, ho! Time for me to buzz off! Just remember: follow the rules, and you won’t end up on national TV in a god-damned fairy suit!”
1This is parallel to the First Law of Chemistry which states: Yes, the Glass is Hot