Jon Corzine, the former head of bankrupt commodities brokerage firm MF Global, has been subpoenaed to testify about his role in the collapse before a congressional committee.

Corzine hasn’t been heard from publicly since MF Global imploded in October, the result of bad bets on European sovereign debt, a risky gamble reportedly pushed by Corzine himself.

The House Agriculture Committee, which is looking into the collapse, will question Corzine at a hearing on Dec. 8.

Federal investigators are still trying to locate as much as $1.2 billion in client funds that disappeared as the investment firm collapsed.

Corzine is a former governor and U.S. senator from New Jersey, who, before entering politics a decade ago, was a co-chair of Goldman Sachs (GS).

In congressional hearings already held, questions have been raised whether Corzine used his extensive Wall Street and political ties to shield his risky strategy from regulators who might have otherwise taken issue with his aggressive bets on the troubled euro zone.

MF Global filed for bankruptcy on Oct. 31, having reportedly gambled $6.3 billion on European debt just as euro zone crisis was hitting its peak. Corzine resigned his post as chief executive of the firm a few days after the bankruptcy filing and hasn’t been heard from publicly since.

Investigators have questioned whether Corzine authorized the use of client money to be mixed with MF Global money to help cover losses as the European debt crisis deepened. Investment firms are barred from mingling their clients’ money with the firm’s proprietary investments.

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