Why was an off-duty policeman encouraging demonstrators to take on his on-duty colleagues?

Via Lenin's Tomb


This chap wasn't really the sort you'd expect to see shouting abuse at police officers at an anti-war demo. He was, after all, a policeman himself - and a high-ranking one at that.

Stop The War has organised about 20 marches in the past, all of which have been peaceful. This is the first where there has been violence.

I cannot say this man was responsible for the trouble, but I saw him try his best to urge the crowd forward.