Why do black people think they aren't rascists too?

It seems to me like alot of black culture, especially black comedy, involves racial stuff. White culture doesn't really involve race much (except for the total bigots, whom i do not even consider people). But you know Richard Pryor, who calls people honkeys and crackers and what not, why is he not considered a rascist? because of slavery? I can see strom thurmond because he is in a position of power and is a rascist, and a lot of outspoken white rascists, of course. I understand that alot of the rascist stuff black people say is supposedly in retaliation for slavery and all that stuff... but is it not STILL rascism? Also on the yahoo boards I see alot of times a black person can say pretty much whatever they want on here about white people - pretty racist stuff- and they are agreed with by alot of people (except you know, white people who spout racist stuff), but if a white person asks an honest question about race then it is inevitable that someone will call them a racist! Whats up!?