My first boyfriend was a paraplegic. We used to go skeet shooting a lot. He owned a .45, .38, and .22 revolvers, and 12 ga. and 20 ga. shotguns. You might be thinking quadriplegic.
Obviously not, thinking more about it. Any really determined shooter could get someone to rig up a gun to be shot by pulling the string-trigger with his TEETH. One could even get it done by sheer body weight pulling on a gerry-rigged trigger.
Where there's a will...
Shows that I haven't given it THAT much thought...until now.