Racism is a powerful factor. The severe disadvantages caused by slavery and segregation remain uncured while programs to adequately compensate for the harm remain to be implemented. Policing has vastly improved in the thirty years since President Johnson's Crime commission identified a wide range of weaknesses that limited the effectiveness of departments in preventing and controlling crime. Officers are better educated. The use of force is more strictly controlled.
Personnel are more representative of the communities they protect.
In fact, the police service may the the most racially integrated institution in the country. The percentage of African American officers compares favorably with that of the general population. African American chiefs have served in a majority of large cities. Yet, the police have not been effective in controlling crime. Their policies have been flawed.