It is out of line, because the suggestion is only being made to the black (or Mexican, or female, or...) judge. Has a white judge ever needed to explain why he

It is out of line, because the suggestion is only being made to the black (or Mexican, or female, or...) judge. Has a white judge ever needed to explain why he didn't excuse himself on a case regarding race? Why not? Why is the white judge the default "impartial" judge, and the black (or Mexican) judge the one who is assumed to harbor bias? (Edit: An in your example, it's really the "active involvement in civil rights struggle" that is more pertinent, not his race. We judge people by what they do, not the color of their skin or the origin of their grandparents.)