FAS

National Security Letters and Administrative Subpoenas (CRS)

03.27.06 | 1 min read | Text by Steven Aftergood

National security letters are investigative tools used in foreign intelligence investigations to compel the disclosure of certain transactional information such as financial records and communications data.

NSLs have become controversial due to their increasing use by government agencies (primarily the FBI), and because of the non-disclosure requirements and the limited judicial oversight involved in their use.

A new report (pdf) from the Congressional Research Service sorts through the five statutes that authorize the use of National Security Letters, including the latest amendments which provide for a measure of judicial review.

See “National Security Letters in Foreign Intelligence Investigations: Legal Background and Recent Amendments,” March 17, 2006.

An abbreviated version of the same report, without footnotes or appendices, is “National Security Letters in Foreign Intelligence Investigations: A Glimpse of the Legal Background and Recent Amendments” (pdf), March 21, 2006.

Administrative subpoenas used in criminal investigations are approximately analogous to national security letters used in foreign intelligence investigations. They are the subject of another new report from the Congressional Research Service.

For extended background on administrative subpoenas, see “Administrative Subpoenas in Criminal Investigations: A Brief Legal Analysis” (pdf), March 17, 2006.

An abbreviated version of that report is “Administrative Subpoenas in Criminal Investigations: A Sketch” (pdf), March 17, 2006.

CRS does not make its publications directly available to the public. Copies of these reports were obtained by Secrecy News.

publications
See all publications
FAS
Policy Memo
Agenda for an American Renewal

There is no better time to re-invigorate America’s innovation edge by investing in R&D to create and capture “industries of the future,” re-shoring capital and expertise, and working closely with allies to expand our capabilities while safeguarding those technologies that are critical to our security.

05.15.25 | 13 min read
read more
Global Risk
Press release
Nuclear Notebook: Russian Nuclear Weapons 2025 Federation of American Scientists Unveils Comprehensive Analysis of Russia’s Nuclear Arsenal

Russia currently maintains nearly 5,460 nuclear warheads, with an estimated 1,718 deployed. This represents a slight decrease in total warheads from previous years but still positions Russia as the world’s largest nuclear power alongside the United States.

05.13.25 | 3 min read
read more
Clean Energy
Blog
AI, Energy, and Climate: What’s at Stake? Hint: A lot.

The stakes are high: how we manage this convergence will influence not only the pace of technological innovation but also the equity and sustainability of our energy future.

05.12.25 | 6 min read
read more
Government Capacity
Blog
Bridging Innovation and Expertise: Connecting Federal Talent to America’s Tech Ecosystems

We’re launching an initiative to connect scientists, engineers, technologists, and other professionals who recently departed federal service with emerging innovation ecosystems across the country that need their expertise.

05.09.25 | 5 min read
read more