The very fact that there is any evidence shows that there is at least one good cop in this whole mess. I was expecting that any video equipment during this event would have had an "unfortunate malfunction" and we would have had to rely on the word of officers instead of our eyes and ears.
I doubt that the shooting was against any policy. More and more the first action by the police in any action is to shoot the dog if it even looks crosseyed at the cops. They just shot the family pooch instead of the dog of someone they could say was a drug dealer or had an address similar to a drug dealer's.