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Each entry provides background and context about an exemption to the public records laws in all fifty states, as well as federal FOIA. Read more about United States of America's public records law or explore all our expert FOIA guides. Have a public records appeal or information on an exemption we should include? Consider sharing your knowledge with everyone by donating your FOIA appeal language.

Glomar Denial

Also known as Glomar Response Glomarization Neither Confirm Nor Deny.

Thank you to Michael Morisy for contributing to this entry. This guide is for informational purposes only, is general in nature, and is not legal opinion nor legal advice regarding any specific issue or factual circumstance.

In the 1970s, investigative reporter Harriet Ann Phillippi sought documents on the USNS Hughes Glomar Explorer, a large salvage vessel built for the Central Intelligence Agency that was trying to find a sunken Soviet submarine. Ultimately, the courts decided that the information was exempt, creating the precedent that even denying a program existed could, in some cases, provide clues as to classified information and programs.

Subsequent rules have affirmed that agencies “may refuse to confirm or deny the existence of records where to answer the FOIA inquiry would cause harm cognizable under a FOIA exception” (Wilner v. Nat’l Sec. Agency, via FOIA.Wiki).

The CIA’s strategy of non-denial has since taken hold at a number of less secretive agencies, including the USCIS and the Centers for Disease Control and Prevention, the Internal Revenue Service, and even local agencies.

Key Citations

Phillippi v. CIA