Ah, rioting because a gang member was killed by police. Why don't people care when it is the other way around? Just because some select police members are allowed to kill in only the most extreme and completely justifiable scenarios (such as when a gangsta is shooting at you and others around you, and if you don't put him down he will put others down - o look, same scenario...) doesn't mean when it does happen you're allowed to riot! If I ran the state I would've stopped the peaceful protest straight off the mark, as there was already an investigation initiated.
But hey ho, if you wanna have a good riot, you might as well pick something unjustifiable and throw shit on top of it, so it looks as though rioting, because a policeman killed someone who was trying to murder others, is in fact the only sensible option available, rather than...say...letting the police do their fucking job.
Funny world we live in. You'll never get a demonstration at a gang's hideout when a cop gets killed. Saying that, the last cop killer I remember was that Raul Moat guy, and he was branded a legend by us Brits in closed quarters. And more investigation went into how he got killed in the end than to go "Welp, doesn't exactly matter. He was a murderer, what's done is done."