You're literally just describing a chicken-and-egg problem. Curious what your brain thinks is the reason African-American communities are policed more intensely. Surely every police organization in the United States is just racist.
I mean their officers keep getting caught posting racist shit, participating in racist chats, police unions regularly donate to republican politicians, and they murder black people so often that the phrase “driving/walking while black” is common slang for when the aforementioned African Americans get gunned down for every day misdemeanors.
So, every police institution? I’m sure there are exceptions, but there’s enough of a preponderance to safely assume it and the data bears that out.
So there is data on some policing in NYC. Because the police need to record stop and frisk encounters, it turns out that black populations get stopped and searched at 2-3 times the rate that other racial groups get stopped and frisked (whites got 10% of the encounters despite being something like 33% of the pop and black+latinos got 90% of the encounters). And it's not like the frisks turned up anything, with the vast majority (90%) of the frisks finding nothing. I believe there's similar data for police in other cities.
At the very least, this suggests that police in NYC and probably elsewhere were disproportionately singling out Black (and Latinos) for intrusive searches without evidence and on a pretextual basis.