The Senate’s confirmation hearing for Judge Michael Mukasey’s nomination to be attorney general opened this morning with largely genteel questioning in which most senators focused on what they perceived to be the past sins of the Justice Department and the recently resigned attorney general, Alberto Gonzales.

In response to questions from the Judiciary Committee chairman, Senator Leahy of Vermont, Judge Mukasey forcefully repudiated a 2002 Justice Department memorandum that was later withdrawn and which critics have said authorized torture.

“The Bybee memo was worse than a sin, it was a mistake,” Judge Mukasey said, referring to the policy guidance issued by the then-director of the Office of Legal Counsel, Jay Bybee. He is now a judge on the 9th Circuit Court of Appeals.

Judge Mukasey also underscored the need for America to retain the moral high ground on the issue of torture. “It’s antithetical to everything this country stands for,” he said. Noting that American troops freed victims of torture from Nazi concentration camps in World War II, the judge added, “We didn’t do that so we could duplicate it ourselves.”

Judge Mukasey said the importance of getting such legal opinions right was not strictly a moral imperative, but also a necessity for the CIA personnel and others who need legal guidance to do their jobs. “We can’t expect them to put their careers and their freedoms on the line if they don’t have confidence that the authorizations given to them are sound,” the judge said.

In response to questions from Senator Kohl of Wisconsin, Judge Mukasey promised to stamp out all political influence over prosecution decisions and hiring. “Any attempt to interfere with a case is not going to be countenanced,” he said. “Hiring is going to be based solely on competence, ability, and dedication and not based whether somebody has an ‘R’ or a ‘D’ next to his name.”

One of the few criticisms of Judge Mukasey came from Senator Feingold of Wisconsin, who complained that the judge would not offer a clear position on whether a president might sometimes be able to conduct surveillance outside the procedures set up by the Foreign Intelligence Surveillance Act of 1978. The issue could bear on whether warrantless wiretapping programs authorized by President Bush were lawful.

“I find your equivocation here somewhat troubling,” Mr. Feingold said. “Congress has spoken.”

Judge Mukasey said he could not comment on the specifics because he was not privy to details of the classified surveillance efforts.

Judge Mukasey, a native of the Bronx, was introduced by Senator Schumer and Senator Lieberman of Connecticut. Mr. Schumer praised the judge as “illustrious” and respected even by litigants whose arguments he rejected. Mr. Schumer also recounted asking Judge Mukasey whether he would say “no” to President Bush if the law dictated such an answer.

“Judge Mukasey then looked me in the eye and assured me, ‘Absolutely. That is what I am there for,'” the senator said.

“This is man of the law, not of politics,” Mr. Lieberman, who attended Yale Law School with the judge, said. “It is hard to think in recent memory of a nominee for attorney general who comes to the office … with fewer political and personal contacts to the president who has nominated him than Judge Mukasey.”

While nominees are normally introduced by the two senators from their home state, Senator Clinton was not present as Judge Mukasey began his testimony today. A spokesman for Senator Clinton cited a “longstanding scheduling conflict” presented by another committee hearing she was chairing today.