Have you seen the Video?
No and I really should have made the effort by now.

racism on the part of the rioters
It's an interesting take on it but there's some truth there. As I've said, though, I don't think they're really rioting in response to this event. Rather they're rioting in response to a pent up frustration. At that point it doesn't really matter whether this shooting was justified or not, the fact that it loosely fits the bill is enough of a spark to kick things off. There's no rationality to this.