The USA PATRIOT Act amended three of the four existing NSL statutes and added a fifth. In each of the three NSL statutes available exclusively to the FBI—the Electronic Communications Privacy Act section, the Right to Financial Privacy Act section, and the Fair Credit Reporting Act section (§505 of the USA PATRIOT Act)
expanded FBI issuing authority beyond FBI headquarter officials to include the heads of the FBI field offices (i.e., Special Agents in Charge [SACs]); eliminated the requirement that the record information sought pertain to a foreign power or the agent of a foreign power; required instead that the NSL request be relevant to an investigation to protect against international terrorism or foreign spying; and added the caveat that no such investigation of an American can be predicated exclusively on First Amendment-protected activities. NSL Amendments in the 109th Congress

Both USA PATRIOT Act reauthorization statutes— P.L. 109-177 ( H.R. 3199 ) and P.L. They provided for judicial enforcement of the letter requests and for judicial review of both the requests and accompanying nondisclosure requirements. They established specific penalties for failure to comply or to observe the nondisclosure requirements. Finally, they expanded congressional oversight and called for an Inspector General's audit of use of the authority. The report is somewhat critical of the FBI's initial performance:
[W]e found that the FBI used NSLs in violation of applicable NSL statutes, Attorney General Guidelines, and internal FBI policies. The second IG Report reviewed the FBI's use of national security letter authority during calendar year 2006 and the corrective measures taken following the issuance of the IG's first report. The second report concluded that the FBI's use of national security letters in 2006 continued the upward trend previously identified; the percentage of NSL requests generated from investigations of U.S. persons increased from 39% of all NSL requests in 2003 to 57% in 2006; the FBI and DOJ are committed to correcting the problems identified in IG Report I and have made significant progress; and it is too early to say whether the corrective measures will resolve the problems previously identified. NSLs in Court

Prior to amendment, two lower federal court cases had indicated that the NSLs and practices surrounding their use were contrary to the requirements of the First Amendment. A federal district court there agreed with the Second Circuit that the NSL confidentiality and judicial review provisions were constitutionally suspect. Recommendations of the President's Review Group

In the wake of leaks relating to the National Security Agency's (NSA's) purported bulk meta-data collection program, the President established a Review Group on Intelligence and Communications Technology. Several of its recommendations addressed NSLs. It eliminates the prospect of Section 215-like bulk metadata collection under NSL authority. Finally, it augments existing reporting requirements for greater transparency. The USA FREEDOM Act handles the judicial review of nondisclosure orders with complementary amendments to the NSL statutes and to Section 3511.
Five federal statutes authorize intelligence officials to request certain business record information in connection with national security investigations. The authority to issue these national security letters (NSLs) is comparable to the authority to issue administrative subpoenas. The USA PATRIOT Act (P.L. 107-56) expanded the authority under the original four NSL statutes and created a fifth. Thereafter, the authority was reported to have been widely used. Then, a report by the Department of Justice's Inspector General (IG) found that in its use of expanded USA PATRIOT Act authority the FBI had "used NSLs in violation of applicable NSL statutes, Attorney General Guidelines, and internal FBI policies," although it concluded that no criminal laws had been broken. A year later, a second IG report confirmed the findings of the first, and noted the corrective measures taken in response. A third IG report, critical of the FBI's use of exigent letters and informal NSL alternatives, noted that the practice had been stopped and related problems addressed.
The USA PATRIOT Improvement and Reauthorization Act (P.L. 109-177, and its companion, P.L. 109-178) amended the five NSL statutes to expressly provide for judicial review of both the NSLs and the confidentiality requirements that attend them. The sections were made explicitly subject to judicial enforcement and to sanctions for failure to comply with an NSL request or to breach NSL confidentiality requirements. Prospects of its continued use dimmed, however, after two lower federal courts held that the absolute confidentiality requirements and the limitations on judicial review rendered one of the NSL statutes constitutionally suspect.
The President's Review Group on Intelligence and Communications Technologies recommended several NSL statutory adjustments designed to eliminate differences between NSLs and court orders under the Foreign Intelligence Surveillance Act ("§215 orders"), including requiring pre-issuance judicial approval of NSLs. Instead in the USA FREEDOM Act, P.L. 114-23 (H.R. 2048), Congress opted to adjust the NSL judicial review provisions governing the nondisclosure requirements that may accompany NSLs. It also precludes the use of NSL authority for bulk collection of communications or financial records. Finally, it adjusts existing reporting requirements to permit recipients to publicly disclose the extent to which they have been compelled to comply with NSLs.
This is an abridged version of CRS Report RL33320, National Security Letters in Foreign Intelligence Investigations: Legal Background, without the footnotes, appendixes, and most of the citations to authority found in the longer report.