I've gone to uncuff someone as antag before in an act of sparing their life, only for them to flash me, harm baton me while I'm in the ground in rest, and then proceed to toss me out into space without a single word.
With the above situation NOT considered power game by everyone else that I talked to in deadchat, I really don't see how what the warden did was worse and somehow wrong; he was enraged by being betrayed by his beloved friends, as they all discussed how to get weapons right in front of him while he sat helplessly in the communal brig.
If I were in his position in real life, I'd chase that fucker down and shoot him in the back too without giving them another chance to betray me.
I mean, I get people can be shocked when they get taken out of the round so suddenly, but I don't see why we have to expect this guy to type a paragraph of dialogue before shooting someone who is clearly: armed and dangerous, conspiring with other crew against the warden, and is capable of turning around, thinking, "Hey that guy should be in the brig" and shooting the warden right back.
There are some points at a round where someone is going to die. Tensions are high, people are very angry, people feel wronged, people feel like others need to face justice, and then people feel like it's up to them to save the day in front of the cute cadet who they want to impress.
I'm with Blizzard. Death happens, it sure as hell happens to me, it sure as hell happens to others , why are we so ludicrously butthurt about our 2D spacemen catching a round in the face without any victim-porn?