One nonpolitical/commercial reminder here.
If any of the four basic safety rules had been applied there would have been embarrassing holes maybe, but no injuries.
Most of us with any experience have screwed up somehow at some point, I'll bet there are a lot of small round holes in things that got there by "I don't know

".
So any excuse is a good reason to remind ourselves that if the weapon is proven to be empty, OPEN THE ACTION AND LOOK, and, NEVER POINTED AT ANYTHING YOU DO NOT WANT TO DESTROY OR KILL, even if it does function with out a finger on the trigger, you only hear a click.
Even if all you do is just NEVER let your muzzle sweep anything but the target, just one of 4 most basic safety rules, you could use a trigger designed by a homicidal maniac and never hurt a soul.
No matter the mechanics the ultimate safety of any thing is between our ears.