Yes, that is the case with redlining, disinvestment, and lets not even get started with them being treated as a nonentity. Interstates and highways were built over and through predominantly black/minority neighbourhoods. White neighbourhoods did not want them because property values, black neighbourhoods weren't even asked.

It's the only race that seems have its own unintegrated subculture

It's so unintegrated white America can't stop adopting it. Rock and Roll was black. Today, you wouldn't be able to tell.

If I were a police officer interested in fining people, I'd head to the rundown parts of the city where the "broken window theory" says more crimes will be committed. And there seems to be more black people there. So I'd probably end up fining more black people than not.

If all you do is look for black criminals, yes that is exactly what you will find.

whatever gives black people a 'black accent' or voice is also what's responsible for the fining and bad subculture.

¿Wait, what!?

black children adopted by middle-class white families don't have this problem.

Oh, they find out soon enough, when being pulled over for "XXXXing while black" the police aren't concerned with who raised you, just the colour of your skin.