They sure can fire people that lose their cool, those people given guns and authority over people. If they can't use that power responsibly, then they should become a rent-a-cop then, no ? They want respect, well accept some tough standards of conduct.
What knowitalls in this thread, anyway ? If you mean me, I've not given any directives on how to raise a kid at all. Even if I was a parent, I'd pretty much still want this cop's head, who cares how angry he is, he has a job and rules for that job.