The Senate Agriculture Committee voted to subpoena former MF Global Holdings CEO Jon Corzine to testify at a hearing next week on the bankruptcy of the company.

The former New Jersey governor and Senator resigned as CEO of the commodities brokerage Nov. 4, just days after it filed for bankruptcy.

Agriculture Chairwoman Debbie Stabenow said the committee has been in touch with Corzine’s lawyer, but he has not responded to the panel’s request to testify.

“We can’t keep waiting. We need definite answers,” the Michigan Democrat said.

The committee agreed by voice vote to subpoena Corzine and other MF Global executives to testify at the Dec. 13 hearing. Stabenow said the hearing is part of an examination of the circumstances surrounding the firm’s bankruptcy — the eighth-largest in U.S. history.

“They can help us get to the bottom of this, better understand what happened and help us to maintain confidence in the futures market,” said Sen. Pat Roberts (Kan.), the top Republican on the panel.

The FBI is investigating possible criminal conduct related to the MF Global bankruptcy. As much as $1.2 billion in client money allegedly was commingled with the firm’s funds — a violation of Commodity Futures Trading Commission rules — and has since gone missing.

Stabenow’s panel is investigating where the money is, how to refund customers, whether the bankruptcy was preventable and whether the rules were appropriately crafted to protect customers’ money. Last week the panel heard testimony from CFTC Chairman Gary Gensler and Securities and Exchange Commission Chairman Mary Schapiro on their oversight of MF Global.

The CFTC on Monday voted 5-0 to approve new rules on investment brokers’ and merchants’ use of customers’ funds — limiting the type of transactions that are alleged to have contributed to the collapse of MF Global.

Roberts said this would be the first time the committee had to subpoena witnesses to testify.

“Unfortunately it is the only option available to us to try and get the answers that so many … demand,” Roberts said.

Last week, the House Agriculture Committee agreed by voice vote to subpoena Corzine for a similar hearing set for Thursday.