A divided US Senate confirmed Michael Mukasey, retired judge, as attorney-general on Thursday, setting aside concerns he might support interrogation methods decried worldwide as torture.

On a largely party-line vote of 53-40 that saw Democrats oppose Mr Mukasey because he refused to declare simulated drowning unlawful, the Senate approved his nomination to succeed Alberto Gonzales, who resigned under pressure in September as the country’s chief law enforcement officer.

Mitch McConnell, Senate Republican leader, brushed off the criticism of the nominee, declaring, “Tonight, a clear bipartisan majority of the US Senate voted to confirm Judge Mukasey because he is one of the most qualified candidates ever nominated to the position of attorney-general.”

Mr Mukasey, 66, a federal judge in New York for 18 years who earlier served as a US prosecutor, initially drew broad support in the Senate.

Lawmakers hailed him as fair and independent-minded nominee and predicted he would restore public confidence in the justice department following Mr Gonzales’s stormy tenure.

But Mr Mukasey ran into trouble at his confirmation hearing last month. He told the Senate judiciary committee torture violated the US Constitution, but testified that he did not know if waterboarding, a widely denounced interrogation method that involves simulated drowning, was unlawful.

In a follow-up letter, Mr Mukasey said he considered waterboarding “repugnant”. But he said he could not rule on its legality until he reviewed confidential US interrogation techniques.

“Judge Mukasey’s answer to the waterboarding question was important in itself, but it also raised for me serious doubts about whether he is prepared to be the truly independent voice that the justice department so desperately needs,” said Harry Reid, Senate Democratic leader.

“If he cannot stand up to the president on such a question of profound importance with a clear legal answer, how can we be sure that he would be more than just another mouthpiece for an administration that treasures secrecy and loyalty above all?” Mr Reid asked.

Critics at home and abroad have accused the US of torturing suspects in the war on terrorism. The CIA reportedly used “waterboarding” while questioning at least three high-level detainees after the September 11 2001 attacks.

President George W. Bush says torture is prohibited but refuses to disclose US interrogation methods. Torture has long been barred by the US criminal code and international treaties.

Mr Mukasey won confirmation by persuading wavering senators. He promised, if confirmed, to enforce any new law Congress passes that specifically bans waterboarding.

Senate critics belittled the pledge, saying as attorney-general Mr Mukasey would be required to enforce all laws and that the controversial interrogation technique has long been illegal.

Patrick Leahy, Senate judiciary committee chairman and a Vermont Democrat who headed Mr Mukasey’s confirmation hearing, led the charge against him.

If another country waterboarded a US citizen, Mr Leahy said, “No senator, no American would have to know the circumstances and the purported justifications for it. We would condemn it.”

Mr Mukasey’s nomination was saved largely by Senator Charles Schumer of New York, a member of the Democratic leadership who had suggested Mr Bush pick the fellow New Yorker and then defended the nominee when he came under fire.

Mr Schumer told colleagues that Mr Mukasey would provide needed leadership at the justice department, which critics charge was demoralised and politicised by Mr Gonzales.

“No one questions that Judge Mukasey would do much to turn around the justice department,” Mr Schumer said. “We should give him that chance. There’s too much at stake not to.”