Not going to say anything that isn't totally obvious here, but the degree to which police feel free to abuse the local population depends on the race and socioeconomic status of the individuals and the neighborhood generally. Take your baton to a rich white person and you might actually face some consequences. Bullets in the back of a young black guy who is presumably guilty of something - we just need to figure out what - and you probably won't.
The only point of racist stop and frisk policies is to find excuses to arrest young black males. If you frisk people you might find weapons or drugs. That's it. Everybody but black people in this country are supposed to be carrying guns on them at all times and disproportionately locking up black people for their drug use is completely racist, even if my local African-American mayor likes to pretend he's unaware of this point.