By Casey Sullivan

NEW YORK, Sept 20 (Reuters) - An attorney for former Dewey & LeBoeuf partners opposed to a $71.5 million settlement with the estate of the bankrupt law firm on Thursday grilled its chief restructuring officer about the legitimacy of the proposed pact.

During a three-hour hearing before U.S. Bankruptcy Judge Martin Glenn, attorney David Friedman questioned Joff Mitchell, who is charged with unwinding Dewey's estate, about his impartiality in crafting the settlement.

More than 450 of 672 former Dewey partners as well as creditors who claim they are owed more than $500 million support the settlement, which would require the attorneys to return $71.5 million in back compensation in exchange for being released from potential clawback claims. If approved by Glenn, the partners would have to pay between $5,000 and $3.5 million each.

Some former partners who object to the settlement have asked Glenn to appoint an independent trustee or examiner to investigate its fairness.

Friedman pointed out that any decision Mitchell made needed to be approved by Dewey's wind-down team, which is comprised of some of the firm's former leaders. Friedman cited a July 12 email sent to Mitchell by former Dewey bankruptcy head Martin Bienenstock in which he tried to persuade Mitchell to reach a quick resolution with the estate.

"I doubt the lenders will fund chapter 11 too much longer," Bienenstock wrote. "But, even if they do, I hope you will promptly move for approval of the settlement while (Dewey) controls the estate's causes of action. That is the only way it can work and the only way it can be done soon. It doesn't matter if (creditors) object."

Mitchell told Friedman he had never replied to Bienenstock's email. He stood behind the proposed settlement, which he described as "rough justice." He said that Dewey's wind-down team had interviewed more than 400 former partners and counsel in preparing the deal.

Friedman opposed the pact in August, because of the composition of the Dewey wind-down team. He said it was managed by lawyers who had advised the firm before its collapse and had given high earners at Dewey preferential treatment when crafting the settlement.

During Thursday's hearing, Friedman also questioned Paul Gendler, a member of Dewey's unsecured creditors committee, about why he chose to support the settlement, which excludes three of the firm's top executives, including former chairman Steven Davis.

The Manhattan District Attorney's office in April launched an investigation into possible financial improprieties by Davis, who has denied any wrongdoing. The office did not immediately return a request for comment on the status of the investigation.

Gendler, whose company Winthrop Resources Corporation is owed $43 million, said he had relied on information provided by the firm's wind-down team, which told him that "the folks that were really responsible for setting the tent on fire are the three folks who are excluded from the (settlement)."

Dewey once employed more than 1,000 lawyers in 26 offices worldwide, but in May it became the largest U.S. law firm to file for bankruptcy. Its demise has been largely attributed to compensation guarantees the firm made to a significant portion of its partners.

Bienenstock did not return a request for comment. The testimony will resume on Friday.

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