[kbenson]

If the premise of the GP is that it's a class/wealth problem, not a race problem, and police disproportionately use excessive force or degrading tactics against the poor, you haven't really provided a counter example. Since black people are more likely to be poor (and racism, institutional and otherwise, likely plays a role in this), you would see more cases of excessive force used against them under this premise.

It's entirely possible, and I think quite likely, that both are occurring. The question then arises as to which is a stronger factor. I suspect that they are close enough in strength that it may change from region to region, city to city.