I have been to a few rallies/vigils/marches lately and all incidences of violence that I have witnessed either in person or through media has been instigated by the police. As far as I know,every documented case where a formerly peaceful crowd turns into chaos has been started with police shooting pepperspray, teargas, or whatever into the crowd.
I find it really hard to not come to the conclusion that the police is desperately trying to set a narrative to justify a history of violence by escalating more violence, but please, someone, restore my faith.
In my neighborhood, the event organizer wasn't even from my city and she was doing everything she could to get the crowd angry at police. Many of the others who spoke were calmer, more reasonable, more positive, sincere, etc, but she was trying to get people ramped up. The police weren't at the protest originally and she tried to use the lack of police presence to anger people ("look, the police don't even care about protecting you!") and then they merely showed up and it was the other way around ("the police are here to stop us!"). Seemed like she was trying to agitate people into provoking the police. Even still, the protest was generally peaceful on both sides; as far as I know, there was no police violence nor rioting/looting/etc. Proud of my hood.