Not trusting the police is common and not really a rap thing. In 90% places on the planet, there are a significant portion of "dirty" policemen. I don't mean stealing drugs and beating up people for no reason. Smaller things like generally taking advantage/not caring for us because they think they can get away with it.
Racial profiling is no joke either. It doesn't matter who you are, how you look, dress or articulate yourself or how many degrees you have on your wall, they just see a black face and assume you're up to no good.
Everyone needs them (especially good cops) but if you call the police over any incident you are probably a CAC.