WASHINGTON – President Bush’s nominee for secretary of homeland security, Judge Michael Chertoff, yesterday said the emotional stress of New York officials contributed to the mishandling of the detention of hundreds of Middle Eastern and Muslim men in the aftermath of the 2001 terrorist attacks.

Testifying at his confirmation hearing before the Senate Homeland Security and Government Affairs Committee, Judge Chertoff sought to play down his role in the controversial sweeps that rounded up 762 noncitizens in the aftermath of the attacks on the World Trade Center and Pentagon.

“I was troubled to see that certainly the plan as conceived had not always been executed perfectly,” said Judge Chertoff. The New Jersey native headed the Justice Department’s Criminal Division on September 11, 2001, and led the federal investigative response that included the sweeps.

Many of the detainees were held on immigration charges for months in Brooklyn and New Jersey without access to lawyers. A June 2003 Justice Department inspector general’s report later found that some were physically abused while in prison. None were ultimately found to have any connection to the attacks.

“I, and I know most everybody who read the [inspector general’s] report, was very troubled by the findings,” Senator Lieberman, a Democrat of Connecticut, told Judge Chertoff.

“I wanted to ask you now, what was your reaction to the report, whether you think mistakes were made in the carrying out of that strategy that you helped devise at the Justice Department?” the senator asked.

Judge Chertoff responded by emphasizing that the action should be viewed in light of the fact that he believed there was a “very serious risk” of additional attacks “worse than September 11.”

Judge Chertoff said he instructed the department to conduct a regular investigation in a compressed time frame and on a large scale. Many investigations were conducted by agents “who had never had prior experience with terrorism,” said Judge Chertoff, who currently sits on the U.S. Court of Appeals for the Third Circuit.

“I understand from the report that there were agents who sometimes, perhaps, took a tip without much foundation and used that as a basis to pursue investigation. I understand that because I know that particularly New York people were laboring under the emotional stress of seeing their colleagues killed under very difficult physical conditions. But clearly, that’s something that’s regrettable,” he said.

Mr. Lieberman said he was “most agitated” by the report’s findings that the detainees were held without access to lawyers, “which is such a fundamental right in the U.S.”

Judge Chertoff said the lack of access to lawyers “was, frankly, not something I was aware of at the time. That is clearly not something that should have happened.”

Most of the men were detained at the Federal Bureau of Prisons’ Metropolitan Detention Center in Brooklyn and at the Passaic County Jail in Paterson, N.J.

The inspector general concluded that the men were kept in detention longer than necessary due to FBI delays in clearing them. The Justice Department required the FBI to clear each detainee before release. Judge Chertoff said he had raised the issue of delays several times.

“The mandate that went out was: Follow all of the leads that are generated by the hijackers and their behavior. For example, if we found pocket-litter in a rental car that had been used by a hijacker and there are phone numbers, follow the numbers,” he said.

If confirmed by the Senate, Judge Chertoff, 51, will become the second head of the sprawling department created after the attacks, replacing outgoing Secretary Tom Ridge.

Senators conducted the hearing in a mostly cordial tone, praising the nominee’s service and willingness to leave a lifetime judicial appointment to take on a troubled department.

Senator Corzine, a Democrat of New Jersey, introduced the nominee, who was accompanied by his wife, Meryl, as “an honorable and impartial man” and “a tough straight shooter.” He was praised for his work investigating racial profiling in New Jersey, and for a career that spanned private practice and public prosecution, including under a former New York mayor, Rudolph Giuliani, in the U.S. Attorney’s Office.

While the judge pledged to protect civil liberties if confirmed, civil liberties groups criticized his testimony about the sweeps, which they said amounted to religious and racial profiling.

“Chertoff set in motion the roundup of more than 700 Muslim, South Asian, and Arab men, but accepts absolutely no responsibility for the bad consequences. Instead, he pins the blame on the FBI and prison officials,” said an ACLU legislative counsel who attended the hearing, Christopher Anders. The Federal Bureau of Prisons did not return a call requesting comment yesterday.

The executive director of the New York Civil Liberties Union, Donna Lieberman, said, “It’s significant that the man in charge acknowledges that there was pervasive wrongdoing. But it’s also noteworthy that his reaction to it is quite consistent with the M.O. of the Bush administration, which is to pass the buck and blame the foot soldiers.”

Neither group takes a position for or against executive appointments.

The senators questioned Judge Chertoff on a variety of homeland security issues, including how he would like to see the department’s grants to states and localities allocated.

Judge Chertoff said he agreed with the September 11 commission’s recommendation that Homeland Security funding should be based “strictly on an assessment of risks and vulnerabilities.” New York City has long advocated for such threat-based funding, but federal funding has been subject to regional battles in Congress. The hearing demonstrated the competing pressures for the money, as several senators took the occasion to press the funding needs in their home states.

Senator Levin, a Democrat of Michigan, also pressed the nominee about his role advising the Bush administration about interrogation policies in the war on terror.

Judge Chertoff said he opposed torture and said the Office of Legal Counsel, in a controversial August 1, 2002, memo, had issued a definition of torture that was “not sufficiently comprehensive.” The memo has since been retracted by the administration, but Mr. Levin pressed Judge Chertoff to clarify whether he was asked to approve it.

The nominee said he was asked by members of the intelligence community to explain how a federal anti-torture statute would be applied by prosecutors. “My bottom-line advice was this: ‘You are dealing in an area where there’s potential criminal liability. You had better be very careful to make sure that whatever it is you decide to do falls well within the – what is required by the law,’ ” he said.

Judge Chertoff declined to say whether his questioners were CIA agents or whether one of the techniques discussed included so-called “water-boarding,” or making a detainee believe he will be drowned.

“I can tell you,” he said, “that whatever was mentioned to me at the time, my answer was exactly the same: ‘I am not in a position to evaluate a set of facts based on a hypothetical circumstance. I will tell you, if you are dealing with something that makes you nervous, you’d better make sure that you are doing the right thing.'”