Sounds like the dog actually served its self defense purpose in chasing off an intruder.
And it seems like the police were messing with the dog afterwards, trying to snare it in a noose. The dog was in an enclosed backyard according to the video and was murdered there by the cops.
Now the police won’t comment or release the evidence of animal abuse (= dead dog).
Doesn’t sound like the dog was out of control to me.
There is no such thing as murder of a damn animal, and anyone that thinks that is nothing more than some Peta whack job. The woman called the cops she had an obligation to control her animal so they could do their job. It was apparently so out of control it would not respond to her.