Affirmative action or fair representation?

Should a police deparment be composed of officers who are representative of the demographics of its community? Is it likely that people are more likely to be abusive towards members of another ethnic group? Would having officers of the same ethnicity assist in the answering of a call help safeguard against abuse?

All things being equal, why shouldn't someone of a specific ethnic background be given "preference" over a white in order to better reflect the demographics of the city? If the deparment reflects the ethnic make-up of a city, is it less likely to be seen as being staffed by outsiders, thus inspiring greater confidence and preserving a better appearance of impartiality?

In megacities are the police more like mercenaries than fellow citizens, since they do not inhabit the areas they patrol? What if the deparment has to hire outsiders in order to meet an ethnic quota, because there isn't enough interest in that city? Doesn't the lack of real connection remain the same, unless there is some sort of natural affection between people of the same ethnic group? Natural affection may help LEOs of a certain ethnicity prevent abuse of his co-ethnics by other LEOs who do not share that ethnicity. But what positive motivation exists to prevent abuse and misconduct?

What if a certain ethnic community cannot police itself, nor produce qualified recruits for the department because it lacks the "moral resources" to do so? Can a police deparment of a big city ever get away from being a form of outsourced help?

Can one be motivated purely by economic/contractual justice to do a good job as a LEO? (I don't doubt that there are many who work as police officers in California merely for the big paycheck and because the job is "fun," despite the paperwork.) What is the foundation that undergirds commutative justice (and prevents abuse), if legal justice or civic friendship is lacking? (1. The officer lives elsewhere. 2. The city in which he works is too large or community does not actually exist there.) If there is no community, then neither virtue cannot exist.