Met Commander Bob Broadhurst responded to criticism of the police on the Today programme:
"We always look to our powers to try and quell violence before it happens. Our plan failed in parts but I think probably our plan prevented much wider violence and disorder.
"If you look back to what it said on the internet beforehand they had a plan to target practically every premise in London. We had a plan that did our best to respond to wherever they went.
"Had we had powers and knowledge and evidence that people were conspiring to commit criminal acts we'd have moved early.
"Everybody has a right to peaceful protest, we have to bear in mind that. These people came along on the day, we'd looked as far as we could, we didn't know who these 500 are. We have to take it that they're going to come and protest peacefully. Our plan was as flexible as it could be while allowing people their rights.
"I think the powers we've got are probably adequate. What we can never cater for are a small number of people who are willing to openly flout the law, and in front of television cameras, cause violence, hurt police officers, just for their own cowardly and selfish ends.
"With rights comes responsibility, unfortunately there's a small number of people that didn't show the same responsibility as the quarter of a million people who show that you can come and protest peacefully."