Britain is already the most tightly surveilled country in the world, according to civil liberty groups and security experts, with an estimated 4 million closed-circuit television cameras spying on roads, buildings, stations and shops.

Not only does that equate to one camera for every 14 people, it also means that in a major city like London--where CCTV is ubiquitous--people run the possibility of appearing on camera up to 300 times a day as they move around.