The FBI is abusing the powers given to it under the Patriot Act in a way that is stifling the current debate about reforming that law, says the American Civil Liberties Union.

"The FBI continues to use the gag order provision of the Patriot Act's national security letter (NSL) statute to suppress key information about the agency's misuse of NSLs," the group said in a statement released Wednesday.

National security letters (NSLs), created under the Patriot Act security bill that was passed in the aftermath of 9/11, allow the FBI to demand sensitive information about users of facilities like libraries and Internet service providers, and then bar those organizations from revealing that the order was ever given.

The ACLU's claim comes weeks after Senate Democrats introduced the Justice Act, an omnibus security bill its authors, including Sen. Russ Feingold (D-WI), say is designed to protect civil rights threatened by the Patriot Act.

Several elements of the Patriot Act are set to expire at the end of the year. The Obama administration has backed the renewal of three of those elements.

The ACLU says the FBI's continued use of gag orders is making it impossible for the public to evaluate how national security letters have been used, and what needs to be done to fix them.

The group is challenging the NSLs in a lawsuit known as Doe V. Holder, in which an Internet service provider is fighting the gag order placed on it by the FBI, in a case it says was misuse of government power. Because of the gag order, very few details are known about the case. The public does not know who the Internet provider is, or what the gag order is related to.

In 2008, a federal court of appeals ruled that the FBI could not maintain the gag order without giving the court a justification for it. Earlier this year, the Obama administration decided not to challenge that ruling, and the FBI complied by handing over a justification.

But, as Jon Stokes reported at Ars Technica, the FBI reported to the judge in secret. Not even the defendants knew what justification the FBI gave for demanding information from the Internet provider. The ACLU challenged that in court, and the court allowed parts of the FBI's justification to be made public.

"One of the legal documents recently made public reveals that the FBI continues to use the gag order to prohibit the disclosure of an 'attachment' to the NSL Doe received that, if disclosed, would show that the FBI tried to obtain records that it was not entitled to obtain under the NSL statute," the ACLU says.

"The FBI's misuse of its gag power continues to prevent NSL recipients like Doe – who have the best first-hand knowledge of the FBI's use and abuse of NSL power – from participating in the Patriot Act debate in Congress," ACLU staff attorney Melissa Goodman said in the ACLU's statement.

"The gag power has allowed the FBI to manipulate the debate, to suppress evidence of its misuse of the NSL power, and to deprive Congress and the public of important information it needs to inform whether these intrusive surveillance and gag powers should be reformed."