An anecdote about a wife beating husband to paint ambassadors "as those who live above the law" confirms only that a-holes are everywhere.
First off. Diplomatic immunity IS THE LAW. And it's the law pretty much everywhere and goes back not less than 3000 years. For a whole bunch of really good reasons.
Maybe you could read up on what has happened historically when diplomats have been mistreated, starting with the annihilation of the Khwarezmian Empire. Never heard of the Khwarezmian Empire? It's because they screwed with Genghis Khan's diplomats.
I would suggest that as a species, Diplomats are a lot less prone to violence as they are often picked for being pleasant and competent with significant negotiating abilities.
The USA has a thousand different kinds of cops and there are millions of laws to ensnare....anybody.
I have an anecdote too.
I've was a passenger in a car with a diplomat girlfriend of mine and got pulled over doing 35 in a 20 mph speed trap by a cranky, rude, condescending, interrupting cop. No other cars for miles
Cop, before receiving the results from running the license plates:
"Lady. Do you know how fast you were going?"
My girlfriend: "No." "How fast I go?"
Me: I couldn't help but chuckle. Just about the same time I could hear a dispatcher yelling at the cop to leave us alone.
My girlfriend told me that if I married her, I'd get diplomat plates and a holo license from the state dept too. I thought about it, but she made a weird slurping noise when she ate. Plus I liked her Mom better.
"Timid men prefer the calm of despotism to the tempestuous sea of liberty" TJ