Without comment, the high court refused to hear an appeal by civil liberties and other groups asking the justices to review whether the secrecy surrounding the arrests and detentions violates the Freedom of Information Act and constitutional free-speech rights under the First Amendment.
In rejecting the appeal, the justices let stand a 2-1 federal appeals court ruling that disclosing the names could affect national security and help "al-Qaida in plotting future terrorist attacks or intimidating witnesses in the present investigation."
The appeals court said the government could also keep secret the dates and locations of the arrest, detention and release of all detainees, including those charged with federal crimes, and the names of the lawyers representing them.
According to media accounts, the majority of the estimated 700 detainees involved in the appeal are Arabs or Muslims and have since been deported. Some picked up after Sept. 11 were charged with crimes, and others were held as material witnesses and interrogated.
The only person currently being prosecuted in connection with the attacks is Zacarias Moussaoui, who was detained before Sept. 11.
Twenty-three news organizations and media groups also joined in asking the high court to hear the case.
"The Justice Department is keeping the names secret to cover up its misconduct," said Kate Martin, director of the Center for National Security Studies, a Washington study center involved in the lawsuit challenging the government.
"The Justice Department is keeping them secret to cover up the fact that they rounded up innocent Arabs and Muslims instead of suspected terrorists," Martin told the Associated Press.
Justice Department lawyers said releasing a list of people interviewed and detained would provide terrorists with "a road map" of the investigation.
Disclosure also could "expose the identified individuals to harassment and intimidation and could destroy any ongoing intelligence value they might have," the lawyers said.
The decision marks a victory for the Bush administration, which has been dealt some earlier blows by the high court's decisions to hear other terrorism-related cases. Those cases include appeals from foreign detainees held in Guantanamo Bay, Cuba, and from Yaser Hamdi, a U.S.-born Saudi who has been detained in a military jail in the United States since his arrest in Afghanistan in 2001.