I think you missed another important difference between writers and cops. Writers, by writing, create. They create a product that may actually be very beneficial to certain people in terms of education, entertainment, or enlightenment. Cops, on the other hand, mostly destroy. They destroy families by abducting mothers and fathers; they destroy minds by cramming people into concrete boxes; they destroy bodies with their weapons and their prerogative to use them. They destroy by acting as agents of the state, itself a massive black hole of destruction.

I myself have a pet theory that any action anyone undertakes can be viewed along this sort of spectrum of creation and destruction. One should live their lives trying to keep themselves as deep on the creation side of the spectrum as possible, and society as a whole benefits when we have more creators and fewer destroyers.