Mueller went on to urge lawmakers to approve the renewal of three PATRIOT Act spying provisions due to expire at the end of the year. The measures allow the government to collect a wide range of financial and personal records, as well as monitor suspects with roving wiretaps.

FBI Director Robert Mueller: “Those provisions have been very essential to us, particularly the first two, which relate to the business records provision and, secondly, the roving wiretaps. And a third, while it has not been used, on lone wolf, is — will be and is important, if we get a similar situation that we had with Moussaoui in 2001. So, I would urge the reenactment of those provisions.”

As Mueller advocated the extension of PATRIOT Act spying powers, the American Civil Liberties Union accused the FBI of misusing those powers to help stifle debate over their renewal. The ACLU says the FBI has used a PATRIOT Act provision allowing it to issue gag orders on its use of National Security Letters, or NSLs. The FBI can gather personal information from libraries, internet service providers and others, while barring those institutions from revealing their disclosures. ACLU staff attorney Melissa Goodman said, “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.”