The head of the International Monetary Fund Christine Lagarde is to appear soon before senior French judges over an investigation into allegations that as French finance minister she was involved in 'aiding and abetting falsification', Mediapart can reveal. The IMF boss is also facing claims that she was involved in the 'misappropriation of public funds'. The affair concerns the controversial decision to use an arbitration process that in 2008 awarded French businessman Bernard Tapie a 403 million-euro payout from the public purse. Lagarde's lawyer is due to learn later this week whether she will be heard as an 'assisted witness'- or be formally placed under investigation. Laurent Mauduit reports.