the west Babylon precinct covers babylon, deer park, and parts of farmingdale.
What police precinct is known as "Fort Apache" (as portrayed in the movie)
Certainly. You can even name officers and officials, as long as you do not depict any of the story's activities as involving them, or quote anything other than actual statements taken in context.
Yes, but it is rare.
In the UK, Directorate of Professional Standards. In the USA, it's the Department of Internal Affairs.