Five former U.S. Treasury secretaries who have served both Republican and Democrat presidents have jointly called on Congress to implement the so- called Volcker Rule to limit the size and trading of banks.

When a congressional panel convened a hearing on the government rescue of American International Group Inc. in January, the public scolding of Treasury Secretary Timothy F. Geithner got the most attention. Lawmakers said the former head of the New York Federal Reserve Bank had presided over a backdoor bailout of Wall Street firms and a coverup. Geithner countered that he had acted properly to avert the collapse of the financial system.