An MF Global executive who has become a central figure in the desperate shifting of funds before the brokerage's collapse, refused to answer questions from Congress on Wednesday, frustrating lawmakers probing why an estimated $1.6 billion of customer money is missing.

The failure of Assistant Treasurer Edith O'Brien and her MF Global colleagues to clear up how the money seemingly vanished drew considerable mocking from lawmakers, who alternated between anger and disbelief.

Appearing before the investigations panel of the House Financial Services Committee, none of the four executives, who also included a senior lawyer and two top finance officials, explained why the money is missing or who was at fault.

MF Global descended quickly into Chapter 11 protection last October 31 after several frantic days of shuffling money between accounts and failing to find a buyer. Chief Executive Jon Corzine resigned four days later.

Bonnie and Clyde, they were chumps, said Steve Pearce, a New Mexico Republican and panel member, referring to the 1930s bank-robbing duo. You guys have people send things electronically ... and nobody's responsible, and you can't even declare that it was robbed or stolen.

O'Brien, a demure brunette dressed in a somber black suit, was excused after invoking her constitutional right against self-incrimination.

She had been the star witness after the panel last week released details of an email from her that said a $175 million transfer made last October 28, and which may have included customer funds, was Per JC's direct instructions.

Unlike O'Brien, Corzine gave exhaustive testimony late last year at multiple hearings, and consistently said he never intended to break any rules and did not give instructions to misuse customer funds. Raiding customer funds is a violation of federal regulations.

Corzine, a former U.S. senator and a governor of New Jersey, did say, though, that others could have misinterpreted directions to fix a fund shortfall.

Corzine had specifically named O'Brien on December 15 before the financial subcommittee, saying she assured him that the October 28 transfer was proper.

MF Global General Counsel Laurie Ferber told lawmakers on Wednesday that she could not provide much more insight. Obviously there was a terrible failure here of some kind. What it was, I don't know.

INVOKES RIGHT

Such answers were more than panel members got from O'Brien.

On advice of counsel I respectfully decline to answer based on my constitutional right, she told panel chairman Randy Neugebauer when asked whether she gave Corzine assurances that the fund transfer was proper.

The Fifth Amendment to the U.S. Constitution protects individuals from being forced to testify against themselves.

Criticism of the executives was bipartisan.

We had $1.6 billion take a walk, and none of you are aware of it? Representative Stephen Lynch, a Massachusetts Democrat, asked the officials. It is absolutely disgraceful.

MF Global filed for protection from creditors after investors and customers became rattled over the firm's $6.3 billion bet on European sovereign debt and downgrades by credit rating agencies, resulting in a liquidity crunch.

Customers have recovered about $3.9 billion, but many shortfalls remain.

Everyone seems to continually point in Edith's direction, and for her not to provide any information or insight she has, it's really disappointing, said Angela Wisdom, vice president of Wisdom Financial Inc, a California firm that said it is still missing $20 million.

NO SMOKING GUN

There has so far been no smoking gun to suggest criminal intent, although federal investigators have been looking at whether any criminal wrongdoing might have taken place.

The three MF Global executives who answered questions - Ferber; Chief Financial Officer Henri Steenkamp; and Christine Serwinski, former CFO of the company's brokerage unit - revealed they have been talking to the Justice Department, and indicated they have not been offered immunity.

Ferber said she is scheduled to meet with the department on April 6. Serwinski said she talked to investigators twice, while Steenkamp said his lawyers had offered a proffer, describing information he could offer, to all of the regulatory agencies and investigative offices.

Several lawmakers including Massachusetts Representative Michael Capuano, the panel's ranking Democrat, questioned whether the court-appointed trustee for MF Global, Louis Freeh, should be paying bonuses to top executives during the bankruptcy.

Steenkamp responded that nothing has been resolved on bonus payouts, which require court approval.

For all the hard work that we're doing, we're just asking to be fairly compensated, he said.

ASSURED

Investigators are looking at whether any of MF Global's $175 million transfer to an overdrawn MF Global account at JPMorgan Chase & Co on October 28 represented money from customers.

Diane Genova, JPMorgan's deputy general counsel, in written testimony for Wednesday said Corzine assured the largest U.S. bank that matters were being handled properly.

Ferber said she resisted providing broad written assurance to JPMorgan that MF Global was complying with the rules. She said a letter suggesting narrower language was drafted, but not signed.

Serwinski, meanwhile, named O'Brien and Vinay Mahajan, who briefly served as global treasurer for MF Global, as possibly having authority over customer funds.

After testimony ended, Neugebauer said he was unsure whether panel staff had interviewed Mahajan, who could not be reached on Wednesday for comment.

Neugebauer also said more hearings are possible, and that Corzine and O'Brien might be asked again to testify.

Nobody is really off limits, said the Texas Republican.

(Reporting by Sarah N. Lynch and Aruna Viswanatha in Washington, D.C.; Additional reporting by Philip Shishkin in Washington, D.C., and Carrick Mollenkamp and Jonathan Stempel in New York; Writing by Jonathan Stempel; Editing by Tim Dobbyn)

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