The Justice Department (search) had detained fewer than 50 people as material witnesses without charging them in the war in terror as of January and had gained 47 court-ordered delays in notifying people of search warrants, according to documents released Tuesday.
In addition, "fewer than 10" FBI (search) offices have conducted investigations involving visits to Islamic mosques, the Justice Department said. The department also said the FBI does not keep files on information collected at public places or events unless it relates directly to a criminal or terrorist probe.
The new details are part of a 60-page agency response to the House Judiciary Committee's request for information about the prosecution of the war on terror and use of the USA Patriot Act (search) since the Sept. 11, 2001, attacks.
The documents did not include specifics about investigations into library patrons' computer use or book records. But Viet Dinh, head of the Justice Department's Office of Legal Policy, told the Judiciary constitution subcommittee Tuesday that libraries have been contacted about 50 times with court permission as part of post-Sept. 11 national security investigations.
"Libraries and bookstores should not be allowed to become safe havens for terrorists," Dinh said.
Committee Chairman Jim Sensenbrenner, R-Wis., commended the "timing and thoroughness" of the answers, but the panel's top Democrat, Rep. John Conyers of Michigan, said the Justice Department could "have been more forthcoming in terms of the manner in which and how freely the new powers have been used."
The American Civil Liberties Union, which has jousted repeatedly with the Justice Department over the new powers, said the responses still do not provide enough details about the library investigations, whether the FBI is scrutinizing mosque membership lists and other civil liberties issues.
"These are basic, fundamental questions that can and should be answered in an open, democratic society like ours," said Timothy Edgar, ACLU legislative counsel.
The number of material witnesses detained around the country without charges has been a closely guarded secret, with officials repeatedly insisting that the law prevented the names and circumstances from being made public.
But in the documents released Tuesday, Justice officials said that as of January, the number of people detained as material witnesses was fewer than 50, with 90 percent of those detained for 90 days or less and half held for 30 days or less.
The documents do not say how many are still being held as material witnesses, an arrangement prosecutors use with a judge's approval for people believed to have important testimony that might not be obtained otherwise. Sometimes the people are eventually charged, such as the conspiracy and terrorism support case brought in April against software engineer Maher Hawash in Portland, Ore.
The USA Patriot Act, passed by Congress shortly after the 2001 attacks, greatly expanded the government's surveillance and detention powers.
That law was buttressed last year when the secret Foreign Intelligence Surveillance Court of Review backed the Justice Department's position that prosecutors and the FBI could share intelligence and criminal information involving spies or terrorists. Under previous guidelines, the government's criminal and intelligence sides were barred from directly communicating.
The Justice documents say that ruling led to a review of 4,500 intelligence files to determine if they could help bring criminal charges, with the information "incorporated in numerous cases" that were not further identified.
The Patriot Act also gave prosecutors a uniform standard for asking a judge to allow a delay in notifying the target of a search warrant as long as there is reasonable cause to believe notification might compromise an investigation or jeopardize human life.
The documents say officials had sought and been granted such delays 47 times as of April 1, with an additional 248 extensions granted beyond the usual seven-day delay. Similarly, Justice has been granted authority to delay notification of seizures of property and electronic information 14 of the 15 times the power was requested.
The one time a court denied the authority it was determined that photographs of items kept in a storage unit would be sufficient for the government in a credit card fraud case.
There has been considerable controversy over the FBI's ability to enter mosques and gather information in public places, powers given to agents by Attorney General John Ashcroft in new anti-terrorism guidelines issued a year ago.
The Justice documents say that an informal survey of 45 FBI field offices showed fewer than 10 had conducted investigations in mosques since the Sept. 11 attacks. All were "open preliminary inquiries or full investigations," not simply exercises in collecting intelligence.
The documents also seek to tamp down the notion that the FBI is routinely collecting and keeping data about ordinary Americans. "FBI agents who visit public places and events may not retain any information unless it relates to terrorism or other criminal activity," the documents said.