Without even getting into the morality of Aaron's actions (though I think you're a pretty shit person if you don't support them), it's pretty clear that the act

Without even getting into the morality of Aaron's actions (though I think you're a pretty shit person if you don't support them), it's pretty clear that the actions of the prosecutor did contribute to Aaron's death. This means that if the prosecutor didn't take those actions, or took different actions, Aaron would still be alive. Therefore, the prosecutor's actions caused Aaron's death. This is simply an objective fact, independent of any moral framework. The fact that the prosecutor's actions were taken as a part of her "doing her job" doesn't change that they caused Aaron's death. If you agree that it is immoral to cause somebody's death (or at the very least that it was immoral to cause Aaron's death in this case), then the prosecutor's actions were immoral. If her actions are a part of her job, then her job is immoral (and maybe the entire ‘justice’ system needs to be smashed). As for the argument that the prosecutor couldn't possibly have foreseen that her actions would have caused Aaron's death (which I imagine you or somebody else would make): of course she could have. People kill themselves because of shit like this all the time, and you don't have to be an empathic genius to understand how the pressure of facing possibly 30+ years in prison could drive someone to suicide.