I have viewed the video more than once, and it appears that the man is antagonizing the police.

Not a good idea in today's police state.

He knew that he was antagonizing the police, and this is why he placed the dog inside the vehicle.

The man is obviously not blind, and even a partially blind man (me) is able to see that the rear driver side window ot the car is opened enough to permit the dog's exit from the vehicle.

That the dog exited the vehicle from the passenger side rear window illustrates the extent of the dog owner's negligence. The dog had more than one choice of egress from the vehicle, which the dog owner failed to act upon.

I don't like this story any more than you do, but the death of the dog is the owner's fault.