Cloud, have you ever considered the point of view of the cops?

They had 10 seconds to decide between shoot/no shoot. If the guy had had a bomb, then we'd be talking about 50+ causualties and crying about how horrible it is that the cops can't protect the trains. The guy was acting suspiciously, doing thing like coming from the terrorist apartment complex (the cops were watching it after they found that this was where the terrorists came from), attempting to change his appearance, wearing a huge heavy winter coat in the middle of July, and lastly, when they warned him to stop, he ran toward the train, not away from it. Now with only seconds to decide the proper course, they chose to error on the side of protecting the train station from what they thought was a serious threat.

It turns out that they had the wrong guy, but they didn't know that at the time. Had they known that he was innocent, then they should have the book thrown at them. But as far as anyone can tell, they thought he had a bomb, and that he could detonate it unless he was dead.