Did you pick this idea up somewhere else or think of it yourself? I've not heard that concept, and it makes way too much sense.
Which country are you in? Have you checked that statistic or did you assume it?
I gather statistics show USA police are not targeting black people ("damn lie and statistics" though, so I'm Caruso's about that result), contrary to how I imagined it. That doesn't mean there isn't a problem, it possibly means the problem is more concentrated - ie in general the police are doing well, but specific groups/officers are being highly discriminatory.