Very simply. Proposition: The sun does not appear to rise in the West. My compass tells me which way is West and tomporrow morning I observe that the sun appears to rise in the East. Repeat as necessary to form hypothesis that sun appears to rise in the East on each and every day. The negative is proven.I've got an easier method. Since you are claiming that these groups are racist, why don't you first of all tell us the groups involved, and then point to SPECIFIC instances where they have made racist statements, or done racist acts, instead of launching into yet another display of complete absurdity.
Just a hint "racist" has become a polemical phrase meaning being in opposition to the universal creed of the day.