The U.S. Court of Appeals for the Armed Forces on Thursday upheld the high-profile court martial conviction of former Navy Lt. Cmdr. Matthew Diaz, who was sentenced to six months confinement for leaking information from Guantanamo Bay.

In a unanimous, 26-page opinion, the appellate court rejected most of Diaz's appeal. The appellate judges did find the trial judge erred in denying Diaz the opportunity to present evidence about his motives in leaking the Gitmo detention information, but the appellate court concluded this error was essentially harmless.

The fascinating case arose from Diaz's service between July 2004 and January 2005 as a deputy staff judge advocate with Joint Task Force Guantanamo Bay. Diaz provided to the Center for Constitutional Rights the names of some 551 detainees, inside a Valentine's Day card.

Diaz argued that the Espionage Act, under which he was charged, has an "intent to do harm" requirement, whereas he "sought to demonstrate that he intended no harm to the United States and acted only to uphold the Constitution." The appellate panel rejected this argument. Stated the panel:

"(Diaz's) awareness of the potential for harm through the unauthorized release of the data is evidenced by the clandestine manner in which he distributed this classified information...He knew or should have known that the information 'could be used to the injury of the United States or to the advantage of any foreign nation.'"

The appellate panel added that "any noble motives (Diaz) might have harbored, including what he may have thought was in compliance with a Supreme Court ruling, were irrelevant to his intentional act of physically mailing the names of detainees and coding information related to these names."

The court said Diaz should have been allowed to introduce his motives to defend himself against the charge that his conduct violated the oath to behave as an officer and a gentleman, but concluded this was harmless.