Inverted (or reverse) racism means being prejudiced against your own race or valuing other races more than your own. So a black person who hates black people or values another race more than black people is being an inverted racist. Similarly, a white person who hates white people or values another race more than other white people is also being an inverted racist. It is inverted because their racism is being directed against their own race.
When Greg Dyke calls the BBC "hideously white" he is displaying inverted racism.
When Jo Brand says "you can't be racist towards white people", she is being racist to her own kind and therefore an inverted racist. To say that a particular race cannot be looked down on or hated by another race is itself racist and as Jo Brand, a white woman, was saying that about the white race, she was ironically displaying inverted racism.
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