Don't cities with riots, almost always have democrat mayors, councilmen and aldermen? And in turn those people appoint the police chiefs?
If the cop is not charged, riots can be expected. If the cop is charged, but found not guilty, expect riots.
They only outcome which satisfies their appetite for grievance is to find the cop guilty of some sort of misconduct.
The deceased is hardly a "gentle giant" when he roughs up a small shopkeeper on video. And he's hardly a cherub, when he steals cigars from the shop.