Leftists are adamant that two classes of people (since they love to count by class) can't possibly be racists.
Themselves (Leftists) and/or Blacks
If they happen to also be Black and on the Left, this is near ontological certainty that they can't ever be considered as racists.
Ironically, Black Leftists happen to be THE biggest purveyors of racist attitudes among the self anointed Left!
The only other thing you'll never see any Leftist-- Black or otherwise do (@RPJ included) is admit to it.