The volunteer "peacekeepers" with clearly no training for this situation hold the most blame from what I've seen. According to what I could surmise from reports and photos, they shot at a leftist who was non-threateningly carrying a rifle, in an open carry state where protesters have been openly armed a number of times, before even saying anything to him or warning anyone. He was in all black with a balaclava so I understand why they were afraid, really the blame more falls on whoever let them be "security" for such an event that definitely would have had threats against it from chuds.