If dozens of policemen are injured and a couple of police cars burn in a demonstration, and the demonstrators had nothing to do with it, I must say that this a very remarkable coincidence. The police don&#x27;t trip over  like that and get careless with their matches anywhere else, to such a degree.<p>My understanding of the demonstrations is that they were not intended as lawful, non-violent peaceful protests. The organizers wanted to make criminal damage (the &quot;Shottern&quot;), and some of the group were also very intent on violence.<p>The problem here is that anyone who was participating surely must have known what they&#x27;re about to participate, even if many have themselves only wanted to not damage or hit anyone themselves. Just create a crowd where this can be done. And it is indeed hard to decide what level of surveillance is necessary and appropriate to prevent violence and large-scale damage.