I’ve known a few libertarians who were cops, or retired cops, over the years. They’ve been good, very good, for the most part – a few were fakes (fake libertarians, not fake cops!) but it was obvious from the git-go.
Lew Rockwell just published a great story by a libertarian cop (now retired) which is worth reading. John Baeza tells a simple story and shows that it is possible to serve the public without sliding to the dark side. Although he doesn’t point it out, he explains one of the major ways in which law enforcement agencies are corrupt: they think that they exist to make money.
I recommend taking a few minutes to read, and sharing it with others.