His statement that he's fully cooperating with the investigation sounds like something a politician would say. Just cooperate- nothing more needs to be said about it.
I watched some interviews and it seems that the 'rules' aren't standardized, but they damn well better change that. Apparently, this gun has had some misfires in the past and if I were in charge of a movie, I wouldn't allow it on my set.
When I was looking at guns, never having owned one, the first thing I did when picking them up is point it downward and away from anyone (either directly or in a way that someone could be hit if a round ricocheted off of the floor) and made sure it was unloaded and safe. I had done a lot of reading and had fired weapons before but, A) I never did it much, B) I'm not a weapons expert but I always look for good info about shooting & firearm safety and C) I just don't want to have that kind of accident.
When I was working at a stereo store around 1981, one of the local cops came in after a shoplifting call at the Sears across the hall and I asked what he was carrying, because I knew he was a collector. He pulled it out and swept the head of one of the other salespeople and was immediately tuned up for it. I don't care if he had fired five million rounds and if it had been made safe, he should have been more careful.
On a lighter note, the officer had arrived at the station that morning & told to go on bicycle patrol in a nearby park because of an attack that had occurred but he wasn't really prepared for that WRT clothing. He came in wearing faded jeans and denim jacket with a polo shirt stretched over his gun belt, walkie-talkie, handcuffs, gun, etc. As soon as I saw him, I asked "Undercover, eh?".