Quote-"The guy in the car was unarmed--what made the cops believe they needed to open fire on him?"
The perp allegedly tried to run down a cop. So instead of getting out of the way, the cop takes the shot. His compatriots, hearing the shot begin shooting "back". The result is what you saw in the video. At least 1 journalist has done some analysis about these types of shooting.
http://www.sierratimes.com/archive/f...arws082301.htm