Camp Delta is a permanent American detainment camp at Guantanamo Bay, Cuba.

A divided appeals court reversed an order quashing a Guantanamo Bay detainee's subpoena for details of his treatment while held at a Central Intelligence Agency black site in Poland for use in a foreign investigation into his alleged torture.

A panel for the U.S. Court of Appeals for the Ninth Circuit ruled that a district court wrongfully dismissed the detainee's request for a subpoena without taking the time to parse aspects of the discovery that were not deemed state secrets but could result in public outcry.

"While it is essential to guard the courts from becoming conduits for undermining the executive branch's control over information related to national security, these concerns do not apply when the alleged state secret is no secret at all, but rather a matter that is sensitive or embarrassing to the government," wrote Judge Richard Paez of the U.S. Court of Appeals for the Ninth Circuit, joined by U.S. District Judge Dean Pregerson of the Central District of California, sitting by designation.

In 2002, the CIA arranged for the capture of Zayn Al-Abidin Muhammad Husayn, known as Abu Zubaydah, in Pakistan. On belief that Zubaydah was a high-ranking member of Al-Qa'ida, the CIA formally detained him as part of its "enhanced interrogation" program emerging from the 9/11 terrorist attacks. In the first four years of detention, Zubaydah was transferred to several CIA black sites, including one in Poland, where Zubaydah contends he was subject to advanced torture techniques that resulted in the loss of his left eye and brain damage. The Senate Select Committee on Intelligence released a report in 2014 that found Zubaydah was not a high-ranking member of the terror group after all, and Zubaydah is now held at Guantanamo Bay Naval Base in Cuba.

In 2015, the European Court on Human Rights found that Abu Zubaydah was indeed held at a Polish CIA site from December 2002 to September 2003, and torture techniques developed by independent CIA contractors James Elmer Mitchell and John Jessen were used on him. These methods include the use of insects, simulating burying detainees alive and persistent waterboarding, to the point where his diet was restricted to limit vomiting during torture.

After the ECHR ruled that Poland did not sufficiently investigate human rights violations against Zubaydah at the black site, the country reopened an investigation into Polish officials' involvement in his detention. The U.S. denied Poland's request for evidence, which forced Zubaydah and his lawyer, Joe Margulies, professor of law and government at Cornell University, to subpoena Mitchell and Jessen for the probe in Poland.

When the U.S. District Court for the Eastern District of Washington granted the subpoena, the Department of Justice intervened and claimed state secret privilege, citing two declarations from then-CIA Director Mike Pompeo.

The declarations argue that Zubaydah's discovery requests "would tend to confirm or deny whether or not [Mitchell and Jessen] have information about these categories as they pertain to whether or not the CIA conducted detention and interrogation operations in Poland and/or with the assistance of the Polish Government."

The district court quashed the subpoena, agreeing with Pompeo that disclosing this information could jeopardize national security by compromising the trust of foreign governments, limiting the CIA's effectiveness in counterterrorism operations and could spur backlash from other countries.

Although the Ninth Circuit agreed that most of the information in the discovery would be state secrets, the court emphasized the need to strike "an appropriate balance … between protecting national security matters and preserving an open court system."

"In other words, the rationale behind the state secrets privilege is to protect legitimate government interests, not to shield the government from uncomfortable facts that may be disclosed or discussed in litigation," Paez wrote. "Protecting the former is an unfortunate necessity in our complicated world of national and international affairs. Protecting the latter is inconsistent with the principle of an independent judiciary."

For instance, the public has known for several years about a U.S. detention facility in Poland and the torture techniques used on Zubaydah and other detainees there, the court wrote, finding that "the district court erred in quashing the subpoenas in toto rather than attempting to disentangle nonprivileged from privileged information."

However, Judge Ronald Gould of the U.S. Court of Appeals for the Ninth Circuit said in his dissent that the majority endangered national security by asking the district court to separate secret information from public information.

"In this case, I would defer to the view of then-CIA Director and now Secretary of State Michael Pompeo that the disclosure of secret information in this proceeding reasonably could be expected to cause serious, and in many instances, exceptionally grave damage to U.S. national security," Gould wrote.

On appeal, Zubaydah was represented by Jerry Moberg of Jerry Moberg & Associates in Ephrata, Washington, as well as David Klein and John Chamberlain of Pillsbury Winthrop Shaw Pittman in Washington, D.C. Klein directed comments to Margulies.

"No country can hide its bloodstains forever, and today's decision was the first step in a long process of coming clean," Margulies said. "We have not yet learned the whole truth about the torture scandal, but this is a beginning. We are also grateful that the panel recognized both that Abu Zubaydah had no connection to al-Qaeda, and that he was not merely subjected to an 'enhanced' interrogation. He was tortured."

Thomas Byron III, a law professor at Georgetown University, who argued on behalf of the U.S. government did not respond to a request for comment at the time of publication. A DOJ representative said the agency was reviewing the ruling.