I'm pretty skeptical when I here of "accidental discharges" and the "I never touched the trigger" excuse.
Yes, it is possible for any mechanical device to malfunction and I'm not saying it can't happen, but I think this is truly a VERY RARE circumstance. Kind of on the same frequency of getting struck by lightning.
I generally think the term "accident" is very much overused in society. Most of the time there is negligence involved, which makes it NOT an accident.