Over the last five years, a global system of tax evasion and havens, worth up to €30 trillion, or half the world's wealth, has been laid bare, thanks to a combination of banking whistleblowers, intelligence agents, eager prosecutors, reforming politicians and an angry public.One of the figures at the centre of these events is a Franco-Italian whistleblower. In 2008, Hervé Falciani left his job at ...