Ooph, if the live gun thing is true that is SSSOOOOOOOOOOOOOOOOO bad.
So a couple of scenarios with guilt being attributed to different things
1. Alec has a live gun (fail on the armorer) and shoots it recklessly (if the "one more take and I'm gonna shoot you" thing has any validity) towards the film crew (Alec goes to jail).
2. Alec was pointing and operating what he and the film crew thought was a blank gun appropriately according to the shooting script, but the live round penetrates the safety screen or whatever and kills the woman. 100% armorer fail but may also be a basic camera team safety fail as they were downrange of a live fire event and their safety measures were not sufficient in the event of a live round discharge.
3. Alec was rehearsing or WASN'T supposed to use a hot gun at all, just a rubber dummy or a non-firing/unloaded prop so there weren't the safety protocols needed for a live shoot, and he squeezed the trigger deliberately according to script, accidentally in a direction he wasn't supposed to (a negligent discharge in shooting parlance), or goes off script and pulls the trigger. Varying levels of blame for Alec but still almost 100% on the armorer.
The lesson learned here, for me anyway, is that we should be using CGI not to mimic firing, but to hide more significant safety markings on various film weapons. Non-firing "training" guns are usually blue so everyone can easily tell. This is something that could be easily edited over in post so actors and crew can more easily see when a weapon is a true dummy gun versus a potentially dangerous tool on set, kind of like how CGI can be used to remove wires and safety harnesses so cast can do more practical stuntwork rather than using CGI to totally replace humans entirely. I think the proliferation of CGI muzzle flashes has allowed movies to show much more dynamic and close range shooting (John Wick is a good example of this, none of that shooting while wrestling choreography would be safe if the gun actually did something) and film crews might be losing some of the expertise that made real blank guns safer on set.
Fucking tragic all around and I hope Alec at least learns some humility from this and doesn't just crusade against the crew.