Minorities in police departments are under-represented in both cities and suburbs. Brookings reports on an article from Governing magazine. “Reporter Mike Maciag found that, on average, people of color on the force were underrepresented by a combined 24 percentage points compared to their share of the local population.”
Allentown, PA had a disparity of nearly 50% between the make-up of its police force and its population as a whole. At the bottom (or top, depending on your point of view): McAllen, TX, where minorities are actually a larger share of the police force than the general population.
Suburbs tend to have larger disparities than the center cities.