Getting the job done

I'd strongly disagree that you "Need more cops like him" but the fact that Kurt Russell made Perry sympathetic and likeable despite everything elevates Dark Blue way above your standard Hollywood cop movie. He did seem to have genuine sympathy for the victims and probably believed he was always doing the right thing- until the end anyway when he realised the riots were "At least partly because of guys like you and me" (that's the great thing about this film- for all the pointless pro or anti LAPD bickering on here it's a film that shows all sides to be not entirely good nor entirely bad). His confessions about all of the corrupt practices he'd been involved in throughout his career at the end was a great moment. As for fitting the wrong man up with a crime just to get a result (and thereby leaving the real perpetrators on the loose), I think any responsible, professional and moral cop would agree that was unacceptable. The unrelated crimes of the man they shot (which he'd already served his sentence for) were irrelevant.