A federal judge lifted a gag order Friday that shielded the identity of librarians who received an FBI demand for records about library patrons under the Patriot Act (search).

U.S. District Court Judge Janet Hall ruled in favor of the American Civil Liberties Union (search), which argued that the gag order prevented their client from participating in a debate over whether Congress should reauthorize the Patriot Act.

"It's fabulous," said ACLU Associate Legal Director Ann Beeson. "Clearly the judge recognized it was profoundly undemocratic to gag a librarian from participating in the Patriot Act debate."

The ruling would allow the ACLU and its client to identify who received the request for records, but Hall stayed her decision until Sept. 20 to give the government a chance to appeal. Prosecutors said they were reviewing the decision.

Prosecutors argue that the gag order blocked the release of the client's identity, not the client's ability to speak about the Patriot Act. They said revealing the client's identity could tip off suspects and jeopardize a federal investigation into terrorism or spying.

Hall rejected the argument that the gag order didn't silence the client.

"The government may intend the non-disclosure provision to serve some purpose other than the suppression of speech," Hall wrote. "Nevertheless, it has the practical effect of silencing individuals with a constitutionally protected interest in speech and whose voices are particularly important in an ongoing national debate about the intrusion of governmental authority into individual lives."

The Patriot Act, passed shortly after the Sept. 11, 2001 (search), attacks, allowed expanded surveillance of terror suspects, increased use of material witness warrants to hold suspects incommunicado and secret proceedings in immigration cases.

More than a dozen provisions of the act are set to expire at the end of this year. Liberals and libertarian-oriented conservatives have pressed for changes, citing privacy and civil liberties concerns.