Ignorance is no excuse, even if your chosen profession doesn't directly involve holding a firearm.

Well said. I also think there is a moral difference between someone with a firearm who plans to use it on another individual and someone making a phone call. That said, I agree, those who support police who also often use violent force instead of more practical/successful solutions like non-violent communication should be held somewhat accountable, just as those support personnel are responsible for the actions they support within the war machine.