First thing they do is arrest them for anything they can get an arrest warrant for fastest. Then they can get them in a room, sweat them, get them turning on each other, get warrants for their phones etc.
Then they can add more serious charges as they gather evidence. Or when higher ups make big strategic decisions like whether to charge them with felony murder because they were part of a crime that lead to the death of a police officer, or to use sedition charges, or the riot act or terrorist legislation because of the bombs.
They won't get off on misdemeanors.