But does it still happen? A big police turnout as a precautionary measure in certain circumstances is sensible. They do that for the Trooping of the Colour too! And just wait 'til you see that royal wedding... I can't tell you the number of times I've been hassled and herded around by dozens of cops whilst attending peaceful demos. It isn't really fair to blame people for something they haven't done, and may not do, just because you see a lot of policemen there. But there has been trouble in the past, so, as I say, taking precautions is the sensible thing to do.