US regulators are set to investigate possible violations of the Sarbanes-Oxley legislation on accounting and corporate governance by former senior management at Fannie Mae, the US mortgage finance company.

The Securities and Exchange Commission, the chief US financial regulator, is expected to determine whether Franklin Raines, former chief executive, and Timothy Howard, former chief financial officer, infringed the legislation's requirements to certify the accuracy of the accounts. Mr Raines and Mr Howard who were ousted by Fannie Mae's board on Tuesday certified that the company's 2002 and 2003 accounts “fairly present in all material respects” its financial condition, in signed statements filed with the SEC.