Remember, Alec Baldwin was not only the actor that pulled the trigger, he was a producer on the show, and a producer that did very little to address the safety concerns that had staff walking off the set, nor did very little to address the eye opening safety failures that had already happened, that foreseeably warned a worse accident could happen.
I think that is why he was charged despite all the explanation its not the actors fault that a firearm they pull the trigger on goes off.....
Not sure if he is directly responsible for hiring the Armorer, her last job resulted in Nicholas Cage walking off set after he almost shot a child, another incident of checking a firearm was unloaded and chamber empty before handing it to the actor, only to find a live round was chambered in the pistol. You've got to wonder, is the girl on drugs? Her appearance certainly doesn't dissuade you of that impression. She only got into the business as a movie Armorer because her father was a very well known movie Armorer with a great reputation. Which might be why she got all the certifications, that otherwise someone in her position would not have..... (I'm not talking good ol' boy network just handing out certifications, I'm talking family business, she picked up enough and with dad's coaching got the certification despite having very little interest and not taking it seriously, which the average person, without the connections not taking it seriously, would never get the certifications)....