One observation about the Shirley Sherrod flap. As soon as the Obama administration and the NAACP got wind of a tape showing reverse discrimination by a black person, they assumed it was true. Sherrod was immediately forced to resign, and the NAACP issued a statement condemning her comments made at one of their meetings.
So why did they jump the gun when doing so ended up hurting them? Because they assumed that it was likely that a black woman had discriminated against a white man. Why would they assume that? Because they know how common it is among blacks to want to help their own over whites. They acted on the assumption that Sherrod was anti-white because they saw it as the smart bet with a black person in power. Whites would probably not make such an assumption, but whites do not know black leaders like Obama and the NAACP do.