Recently I've taken to calling all "law enforcement" goons reavers. That keeps me from calling them things I'd rather my daughter not repeat. And the term is completely appropriate.
"Reave" is from Old/Middle English and means to forcibly rob, which is what "law enforcement" spends most of its time and energy doing. So, by definition, they are reavers.
That brings up a bit of historicity. The word "sheriff" comes from the Old/Middle English for "shire reeve" or "reeve of the shire". The dictionary claims that "reeve" and "reave" are not related words, but I have my suspicions that they are wrong.
I can just imagine some townsfolk, many years ago, saying "Great, here comes the Shire Reave of Nottingham!" He overhears this and gets pissed at them. So they wink at one another and say "Oh, no! We would never call you a reaver; we were calling you the 'reeve', which is totally different! Trust us."