Well but that's sort of the point. I think 99% of the people on earth would be in favor of camera setups like this if there was some way to guarantee it would only be used to catch murderers and rapists. But it's a slippery slope and once you put that power in the Government's hands they will almost certainly abuse it.

You're probably right about the cameras being a permanent fixture in London. But the fact that Government officials are using them more for minor infractions than serious crime is a lesson that may prevent setups like this in other places.