Its funny that you seem to think that all these problems happened after Mike Brown was shot, but the years of police abuse somehow means nothing.
People learned long ago in Ferguson that the police are not on their side, which is something the police have gleefully shown to be true whenever possible. Maybe if the police had been interested protecting and serving instead of seeing the population as a money source, a lot of these problems could have been avoided. But they didn't, so now this is what they get.
Did the city burn before or after Brown?
Did officers get shot before or after Brown?
There were problems at Ferguson, no denial.
It had nothing to do with the DOJ type findings; no one was out on the streets before Brown complaining on the issue.
But people choose to aggravate the issue making it difficult to move forward.
Peoples actions have shown that they want revenge, not healing.
The video captured a voice which clearly demonstrated the issue. Because nothing was done previously, even though Brown was at fault and Wilson not; people felt that a lynch mob should have been done; justice be dammed.