All cops means ALL COPS. I've known friends & family who are great people. Loving fathers, caring husbands, cool dudes all around, but they were none the less cops. If you want to still be friends, great, unless you're discussing potentially incriminating stuff, you're probably fine (but even then there are damn good reasons lawyers tell people, innocent or not, to NEVER EVER TALK TO COPS EVER). This is the kinda thing where a relationship must nessisarily be different from the rest of the group, for the safety of yourselves & others. Don't rat out your friend who's got a hungry newborn & no money for babyfood, for instance. Maybe this difference is for the better, maybe for the worse, that's yours to work out.
All Cops Are Bastards, not nessisarily because they, themselves, as individuals, are bastards. But because of the job itself. What it expects of these people, the mentalities/ideas/trained responses it instills in them, the training & culture, what is expected of them, their responsibilities & tasks, how they are conditioned to perform them, the laws they are paid to enforce & how they're made to enforce them, etc. All of these make them a bastard same as any other cop because THE JOB ITSELF IS A BASTARD.
I won't describe how, there's plenty of info out there, & it sounds like you already have some understanding of it. Here's a link or two anyway.
Bottom line, they can still be a friend. Definitely a different kind of friend than you might be used to, possibly not as close a friend as they might otherwise be, but still a friend. But until they get that pink slip, (i.e, get fired or quit) be careful. If not for yourself, than for the people around you who are vulnerable. People of color, women, homeless, mentally ill or different, queer, activist, even those they are closest to, all of the above & more qualify as such. The power he wields has been used constantly to frustrate the lives of the above since their badge was made of silver, & likely will be for some time to come.
All Cops Are Bastards, because the job itself is.
Toss-up between grenades & drones next