When does diversity equal bias rather than benefit?

Soon after television stations aired a videotape of Shirley Sherrod talking about whether she could overcome her own racial bias to help a white farmer save his farm, further reporting showed the tape had been edited to take her words out of context. The full tape revealed that Sherrod, who is African American, had been telling a story not of sticking it to the white guy, but of how she overcame her own sense of prejudice.