He was running from the police. The police had their guns drawn and were shouting for him to get on the ground. At that moment he began reaching into his bag. That's when the shots were fired.
When a police officer is shouting commands at you with his gun drawn, you do what he says. Period.
To a sane person, absolutely.
To someone bipolar, it matters not what you say. They're not occupying the same "space" as you or I.
We hospitalized my mother (diagnosed bipolar in her 60's) just days before she was to flown overseas. I have absolutely no doubt that she would have been incredibly disruptive and downright scary to the other passengers.
There are no easy answers, but I have to assume that the marshall was acting in good faith.
You can't shoot someone just because they run from the cops. It comes down to whether the skycop thought he said he had a bomb, I think.