as soon as they were in the place of riots, they could be sued for the crime. Additionally, there are so many footage, certainly some would be identified solidly.
i think so, particularly the police gave them hours of advanced notice and warning, giving enough time and a good chance to leave. Why they still stayed?! and it was a fact that the destruction was quite serious at large area of the site.... as long as they were in the scene of crime and they did not stop/leave the crime, there are justified reason to press charge. It is a matter of judge and presentation of evidence...