Even in the annals of Nigerian corruption scandals, the latest revelations about the diversion of state funds under the presidencies of Goodluck Jonathan and Umaru Musa Yar'Adua are breaking records. On 18 January, Information Minister Lai Mohammed announced that 55 people had stolen 1.3 trillion naira (US$6.5 billion) in 2006-13. He said the miscreants included 15 former state governors.

Last year's audit of oil operations failed to explain how at least $10 bn. of export revenue had not been transferred to the Federation Account. Last September, Deputy Oil Minister Emmanuel Kachikwu said international oil companies had been overpaid some $10 bn. through a system of tax breaks and over-invoicing on services costs.
Arms deals were the other favoured means to divert state funds. Investigations of two parallel procurements continue: the first targets Colonel Sambo Dasuki, former National Security Advisor, who is accused of presiding over $2 bn. of fraudulent arms deals which allowed Jonathan's government to fund its 2015 election campaign. Then in another $2 bn. arms scandal, ten generals and a colonel are in the frame for running another corrupt network.

The week's revelations have raised two questions for a nearly unshockable Nigerian public: how far into the heart of the Jonathan government will these investigations go? And most pertinently for the future, where are the institutional constraints to stop the same thing happening again?