The National Security Agency (NSA) blocked the release of a purported tape of Bill Clinton and former Attorney General Loretta Lynch’s private airplane talk with a rare legal justification used to protect top national security secrets.

The NSA’s block of the release of this information — citing one of President Obama’s executive orders — undercuts Hillary Clinton’s claim that her husband and Lynch had a “purely social” conversation about grandkids and golf on June 27, 2016, two weeks before Lynch dropped the Department of Justice investigation into Hillary Clinton’s email scandal.

Citizen researcher Larry Kawa is pressing the government to release the contents of a taping system that is required to have been installed on Lynch’s government airplane. Kawa points to the Tempest system, a NATO-certified system by which the NSA tracks and records sound that emanates within government structures.

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“General Dynamics installs the recorders in the planes,” Kawa told Big League Politics, referring to VoIP recorders that he said must be installed on airplanes like the government jet used by Lynch, where the conversation took place. “(Lynch) could not have un-installed them if she wanted to.”

Kawa’s Freedom of Information Act (FOIA) request to the NSA was denied, citing national security, but the NSA did not deny that the tape exists.

“To respond to your request, NSA would have to confirm or deny the existence of intelligence records on Loretta Lynch,” the agency stated in its FOIA response on November 14, days after the election. “Were we to do so in your case, we would have to do so for every other requester. This would enable, for example, a terrorist or other adversary to file a FOIA request with us in order to determine whether he or she was under surveillance or had evaded it. This is turn would allow that individual to better assess whether they could successfully act to damage the national security of the United States. For such reasons, we can neither confirm nor deny the existence or non-existence of the records you requested.”

After challenging the NSA’s response, Kawa received an email from the NSA FOIA office, stating that he was being hit with a “Glomar” denial.

“Our letter dated 14 November 2016 is indeed our final response to your FOIA request. It states that the “first exemption” of the FOIA authorizes, by Executive Order, properly classified information to be kept secret and goes on to say that the fact of existence or non-existence of intelligence records on any individual is an appropriately classified matter. The “first exemption” is often referred to as the “B(1) exemption” to which you refer,” the NSA stated.

“We also provide background information regarding the decision, as well as the specific paragraph of E.O. 13526 which authorizes the type of response, which is often called a “Glomar” response.   In addition, we state that the withholding of this information is also authorized by the third exemption under the FOIA, as the information is also protected by statute.  Lastly, we provide you with instructions on how to appeal this response,” the NSA stated.

Executive Order 13526 was signed by President Barack Obama on December 29, 2009.