The problem is economic and cultural (we allow for guns) so the police take maximum caution, and given the police are the only expression of government in some areas, the negativity falls on them. It's not as if most of the community in a blighted area don't want police - they do, but they also want police to act as if the areas didn't have a violent characteristic. Any area of the world with high crime, be it Russia, china, France, germany, greece will have police act differently in those communities. It's a reaction to the dynamics in such places. It takes effort to overcome and the local Govs typically don't put in the necessary effort.