And I'm not really arguing either side so much as pointing out that the current disorder and violence is in response to regular police violence. Regular.
No place breaks down due simply to an absence of police. But I've heard of police states -- and those aren't something anyone talking about the merits of order and safety should be arguing for.
1. Police don't just start one day misbehaving without any warning. It takes years to get there, years where they see there is no consequence for being more and more out of line and years of having immunity for their actions.
2. That event was not handled properly, the cop should have been arrested on the spot or in a couple of hours, not days later. These lack of immediate action was seen as an attempt to cover up or minimize the gravity of the situation and that is a very good reason for public protests.
Both #1 and #2 are not the fault of the police, but for people governing over the police force. Quoting from a well known psychologist, the regular policemen has an IQ around 90, the police oversight body should compensate for that.