It's the dark heart of Britain, the place where democracy goes to die, immensely powerful, equally unaccountable. But I doubt that one in 10 British people has any idea of what the Corporation of the City of London is and how it works. As Nicholas Shaxson explains in his fascinating book Treasure Islands, the Corporation exists outside many of the laws and democratic controls which govern the rest of the United Kingdom. The City of London is the only part of Britain over which parliament has no authority. This is ... an official old boys' network. In one respect at least the Corporation acts as the superior body: it imposes on the House of Commons a figure called the remembrancer: an official lobbyist who sits behind the Speaker's chair and ensures that, whatever our elected representatives might think, the City's rights and privileges are protected. The mayor of London's mandate stops at the boundaries of the Square Mile. The City has exploited this remarkable position to establish itself as a kind of offshore state, a secrecy jurisdiction which controls the network of tax havens housed in the UK's crown dependencies and overseas territories. This autonomous state within our borders is in a position to launder the ill-gotten cash of oligarchs, kleptocrats, gangsters and drug barons. It has also made the effective regulation of global finance almost impossible.