It's not just happening "in isolated areas." It's happening across the country and police departments are getting sued for it by individuals and the Justice Department. Even if it were only in isolated areas, that still is not a legitimate defense. The experiece of the man in "Black Like Me" happened at a time when racism was displayed more overtly in public, now it is more subtle and concealed, but the unequal treatment is still occuring in many ways. You might not notice it if you are not the victim of it. Say you are white and you are buying a new car, you get quoted one price, and if the person selling the car has conscious or unconscious racist tendencies, they will quote a higher price for a black person. You never knew it happened because you never saw your price compared to the black person's price, but now studes have shown that this is happening on a mass scale (and it happens to women too, by the way.) When you as a white person go to rent an apartment from a racist landlord, they immediately show you the available units, but if you are a black person, they tell you that no units are available. This happens all over the place, in fact, Donald Trump was sued by the Justice Department for housing discrimination and lost, twice, and that was under a Republican administration. To minimize or ignore this issue is to do a disservice to humanity.