If you want my opinion, the police were trigger happy.
Since we have this information -- Read On Combat, On Killing, and the first chapters of Training at the Speed of Life -- terms like "trigger happy" are of decreasing usefulness in thinking about a deadly force situation.
The upstate returns aren't in on whether the decision to shoot at all was a good one. My impression, though, is that if the guys on the scene truly thought that one of their partners had been hit by a car which subsequently hit one of their cars and showed no signs of doing the legal thing, namely: stopping, then I can see why they thought the compost had just hit the air-conditioner.
I'm not sure they should have reached that decision, but I think I understand it.
But once they did decide it was time to get serious, the number of shots fired is great for headlines, but not especially remarkable when you look at what people really do when things get exciting.
To put it another way, the first shot MAY have been because of being "trigger-happy". The subsequent shots were just what usually happens when things get exciting.
Let me try to say this: I find training with my fire arm demanding but relaxing. I like to go to the range. I like to try to shoot well. But I hate what handguns represent. Since we live in a world where sometimes guns are necessary, I guess I'll step up. But I'd just as soon I did't have to think about gun fights, or sit here with my p239 digging into my butt.
And I can guarandamntee you that, since I have one magazine in the gun and two on my belt right now, if somebody shot at me through the window right now, one magazine would be emptied right away. I HOpe I'd save the others for afgter I'd taken cover and had a clue about what was going on.
Reality is NOT like TV or like the movies. Most of us crap in our pants when things get exciting - literally. That doesn't make for good TV or good movies, so you don't hear about it much, but there it is.