Who is supposed to hold the buggers to account because it does not seem the chief copper has any issues with it. In fact it looks like he gives the order to crack a few skulls himself.
If it is kicking off proper fair enough put your shit kickers on but all the reports seem to be of groups getting steamed into by riot police, With terrorism these days they will no doubt sadly get a few chances do their job and control crowds but no need for the wanton violence doled out.
My ideal is in a square at a designated bar have the cops sat across the way chilling out sure, have the head copper go to the groups head chaps and say 'ok you guys be good and leave us to chat the shit and have an easy night and we will give you no hassle, make us get up and all bets are off and officer Pablo recently caught his wife cheating with an englishman, did i mention he has killed 5 men, you can see him there, that 7ft guy holding the 8ft baton with nails in it'. You get the point, basically a bit more interaction between the two sets before the festivities start so both know the ground rules for that bar at that day.