The FBI asked the Justice Department last fall to seek permission from a secret federal court to use the most controversial provision of the USA Patriot Act, four weeks after Attorney General John D. Ashcroft said that part of the law had never been used, according to government documents disclosed this week.

A one-paragraph memo -- saying the FBI wanted to use the part of the law that allows investigators in terrorism and espionage cases easier access to people's business and library records -- was in a stack of documents the government has released under court order, as debate persists over whether use of the anti-terrorism law violates civil liberties.

The 383 pages of documents, many with names and other information blacked out, are the first results of a Freedom of Information Act request and lawsuit filed against the Justice Department by a coalition of civil rights groups. Last month, Ellen Segal Huvelle, a federal appeals court judge for the District, ordered the agency to release certain documents indicating how the FBI is carrying out the law. She denied the government's request to withhold such information for another year.

The Patriot Act was passed by Congress at the Bush administration's urging six weeks after the Sept. 11, 2001, attacks. The law strengthens the executive branch's power to conduct surveillance, share intelligence with criminal prosecutors and charge suspected terrorists with crimes. Critics have been frustrated that the law allows many of its most controversial powers to be carried out in secret.

The newly disclosed documents, and a second batch the judge has ordered to be issued next month, come as an election-year fight is raging over whether several parts of the law should be extended beyond the end of next year, when they are scheduled to expire. President Bush argues that all of the law should be made permanent, but many Democrats and some conservative Republicans disagree.

The memo involves the provision at the core of that political debate. Until last September, Ashcroft had insisted that the government could not disclose how many times investigators had used the part of the law that allows his agency to get approval from an obscure secret body, the Foreign Intelligence Surveillance Act (FISA) court, which requires less proof than other courts to authorize wiretaps and other surveillance. Ashcroft had repeatedly said that information was classified. But last September, he unexpectedly declassified a memo saying that the provision had never been used.

The newly disclosed memo, dated Oct. 15, shows that an office of the FBI had asked an office at Justice to ask the FISA court to approve a search. The memo does not indicate the nature of the search, whether Justice ever asked the court and -- if so -- whether the court granted the request.

Jameel Jaffer, a staff attorney for the national office of the American Civil Liberties Union in New York, did not accuse Ashcroft of being untruthful in September. But Jaffer said the memo "tells us the attorney general was selectively declassifying information to serve his purposes." He added that the administration did not make public the FBI's request when, late last year, it argued a separate lawsuit over the Patriot Act that the ACLU filed in Michigan.

Mark Corallo, a spokesman for the Justice Department, said yesterday that the disclosed memo does not establish whether the FISA court has ever granted such a request, or even whether the agency forwarded the FBI's request to that court. Asked whether that request -- or any others since -- had been made to or approved by the court, Corallo replied, "That's classified."

Corallo said that in Ashcroft's September memo saying the provision had never been used, the attorney general was "not only . . . being technically accurate. He was being completely accurate."