Critics say a 1984 material witness law was abused by the Justice Department, and by Judge Mukasey and his judicial colleagues, to hold terrorist suspects indefinitely after Sept. 11 without having to accuse them of a crime and afford them the rights of a criminal defendant.

The roundup of men like Mr. Awadallah under the material witness law in September and October 2001 was an early effort by the Bush administration to rewrite or reinterpret laws on the detention, interrogation and surveillance of people suspected of terrorist ties after the Sept. 11 attacks — a campaign that is now the subject of furious debate between the White House and the Democratic leaders of Congress.

Critics say the material witness cases before Judge Mukasey after Sept. 11 offer insight into his performance and temperament at a time of duress. The cases came before him at a time when New York was still in turmoil, with the courthouse in Lower Manhattan, only blocks from the rubble of the World Trade Center, partly shut down and operating under extraordinarily tight security.

Democrats on the Senate Judiciary Committee have said they will try to review cases like Mr. Awadallah’s in detail before Mr. Mukasey, who retired last year after 18 years on the court, appears before them.

Senator Charles E. Schumer, the New York Democrat who encouraged Mr. Bush to consider Mr. Mukasey for the Justice Department job, said that he was aware of the concerns over the nominee’s record on material witnesses cases, and that they would be studied by the committee. “There will certainly be those questions for him,” Mr. Schumer said.

Congressional aides said that while the committee’s chairman, Senator Patrick J. Leahy, Democrat of Vermont, thought it was too early to discuss specific questions that would be put to Mr. Mukasey, the senator has long been concerned about the possible abuse of the federal material witness statute in the indefinite detention of terrorist suspects.

The records of most material witnesses cases are sealed, so there is no way to determine whether Judge Mukasey’s tone in the October 2001 hearing for Mr. Awadallah reflects his handling of other witnesses picked up after Sept. 11.