What I think was after he pulled the guy over, he could have at least called animal control or gotten another officer to take it to a nearby vet, where is the danger in that?
I've seen good cops take animals to a vet before, I was watching Cops once and they took 2 pit bulls to a vet after they got in the way of some crazy man trying to shoot their owners.
and ive seen good cops take a man off the street that was driving at breakneck speed while lacking good judgement.