Right-wing billionaire Robert Mercer, whose fortune bankrolled Breitbart and helped elect Donald Trump, has been using a legal loophole to stash his money offshore and avoid tens of millions of dollars in taxes, according to The Guardian’s review of the leaked documents known as the Paradise Papers. The papers show how Mercer, 71, has apparently used companies in Bermuda to avoid an obscure tax on the investment profits of his family’s shadowy foundation, which is led by his daughter Rebekah. The foundation has used its money to fund Clinton Cash, Steve Bannon’s book project that attacked Hillary Clinton, along with conservative groups like Citizens United and a retirement fund for Renaissance Technologies, Mercer’s own hedge fund. (The IRS has been investigating Renaissance for allegedly avoiding $6.8 billion in taxes.) One of the institutes funded by the Mercers, Bannon’s Government Accountability Institute, lists as its mission to “investigate and expose crony capitalism [and] misuse of taxpayer monies.”