Obviously not a legal expert.
Is Mr Baldwin still not in the hot seat because he is also a producer of the show and because of their penny pinching they hired and incompetent armorer and then gave her extra duties to do on top of of that causing her not to spend as much time and energy doing her primary job?
I recently watched a video, I believe I posted about it in this thread in fact, where they did an interview of a Hollywood armorer. He was actually going to be the one for rust but was passed over because he was too expensive. He stated that there was a standard protocol of how Firearms were supposed to be handled on set. Something along the lines of they are brought in unloaded, the actor, the director, the armorer all verify that it's unloaded, then it is loaded by the armorer with the actor, etc, ETC watching directly.
Then eyewitness interviews of this particular shooting say that that type of activity did not happen on the set.
Thus, is he not liable since he did not follow standard operating protocol? He could have said "whoa, hold on! You need to show me that this gun is indeed cold! "
( not sure if they're truly is an intact protocol for all of Hollywood regarding this.)