Here's an example of a cop standing trial for maslaughter in the Uk, and then getting acquitted

http://en.m.wikipedia.org/wiki/Death..._Simon_Harwood

Which in my view was the right outcome, it was also right that he was put on trial

The pity is that the US doesn't seem to deal with nuances, you either seem to be in the cops are above the law, or fuck da police camps, when its clear that reality is more complicated. And in case you think I'm also guilty of that, I consider the decision not to charge the Missouri cop was correct.