Black Lives Matter?

So do black lives only matter when it's White on Black?
Do they not matter when a black man kills another black man?
Is his life considered "less" valuable by blacks?
Would this not be "racist"?

Cpl. Martinus Mitchum was shot twice in the chest by another black man as he was escorted from a basketball game at Washington Carver High School for (reportedly) refusing to wear a mask.

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