That the progressive nature of a city's electorate generally doesn't reflect in its police/corrections forces; civilian oversight is severely limited and pushed back against. The NYPD was openly at war with it's theoretical executive, DiBlasio, including doxxing his daughter.
I'm not sure it's a matter of political identity here, the police just push back against anything that makes them accountable, they want to be able to kill, maim, and hurt without being questioned.