One issue is that many gun "accidents" like car "accidents" really aren't, or at least not in the way that I think of accidents. At some point the behavior is clearly negligent, whether we're talking about "accidentally" ramming a pedestrian with the clear right of way, or "accidentally" having your gun go off and kill your own kid because you dropped it with the safety off. Just such a tragedy, you know, can't be helped. Somehow for individual behavior this reasoning only seems to apply when guns or cars are involved (excuses for corporate behavior covers just about everything, of course).