All it takes is one cop acting badly to ruin things for quite a lot of people though, and the fact that police uniformly circle ranks around any of their members who is accused of something regardless of the validity makes "well, not all of them are bad!" a pretty useless sentiment. I'll consider them individually when they start holding individuals accountable, but not before then.

I think you're making some hasty generalizations here. They don't "uniformly" cover for their colleagues. Do you expect the police service to be perfect and never make mistakes? Can you point me towards a single human-run service where that's the case?