Panel: Credit raters, regulators failed MF Global

The report also said the Federal Reserve Bank of New York fell short of properly assessing the firm's level of risk before allowing it to join an elite group of firms that help the government sell Treasury securities. That endowed MF Global with a seal of financial strength and gave it a competitive edge.

"This marked the first time in the history of the U.S. futures industry that a customer suffered a loss due to the mishandling of customer funds," Rep. Spencer Bachus, R-Ala., chairman of the full Financial Services Committee, said in a statement.

"These customers deserve to know how and why their money went missing. And all Americans deserve to know that regulators and policymakers are held accountable to prevent similar losses from ever occurring again," Bachus said.

Much of the money belonged to farmers, ranchers and other business owners. They bought and sold financial contracts with MF Global to reduce their risks from the fluctuating prices of corn, wheat and other commodities. In recent months, nearly 80 percent of those funds have been returned.

Republican members of the subcommittee said the panel's staff interviewed more than 50 witnesses and reviewed 243,000 documents from MF Global, former employees of the firm and federal regulators.

Corzine took the top job at MF Global after losing a bid for re-election as New Jersey governor in 2009.

On Wednesday, he disputed through a spokesman the allegations made by the Republican lawmakers. He said he "acted in good faith" at all times and rejected the claim that he ran the firm in an authoritarian manner.