They didn't tase him because he's black, they tazed him because he was reaching to take his backpack off. They probably understood that's what he was doing, but have it ingrained in their tyrant heads that "If he reaches for his waistband, it's ok to fuck him up". The cop who tazed him should be fired and criminally prosecuted for assult with a deadly weapon. The cops who aided in the arrest/didn't arrest that cop should be fired and prosecuted for aiding in a felony.