At issue before the U.S. 7th Circuit Court of Appeals was a government request that it reverse a trialcourt's ruling granting terrorism suspect Adel Daoud's lawyers unprecedented access to secret court records.
Snowden's revelations about expanded U.S. phone and Internet spying and how the Foreign Intelligence Surveillance Court, or FISA court, secretly signed off on them raised the profile of such issues.
Daoud, a 20-year-old U.S citizen, has denied allegations he accepted a phony car bomb from undercover FBI agents in 2012, parked it by a Chicago bar and pressed a trigger. His trial is scheduled to start Nov. 10.
Assistant U.S. attorney William Ridgway said during Wednesday's hearing that Attorney General Eric Holder had formally notified the trial judge before her ruling that opening Daoud's FISA records to his own lawyers could jeopardize national security.
U.S. FISA law "does not allow courts to second-guess (the attorney general's) judgment," Ridgway told the three-judge panel.
But Daoud's attorney, John Cline, argued that the challenge of preparing for trial without the chance to comb through the voluminous documentation submitted with wiretap applications to the FISA court is "like playing pin the tail on the donkey."
The defense has said the FISA records could indicate that expanded surveillance methods led investigators to target Daoud. If so, they could challenge all subsequent evidence on constitutional grounds.
Since Congress created the FISA court in 1978, no defense attorneys had been told they could go through a FISA application until U.S. District Judge Sharon Johnson Coleman's January 29 ruling in Daoud's case.
At the time, she said allowing the defense to vet potential evidence would help guarantee Daoud's right to a fair trial. She said the fact that no judge had ever granted such FISA access before wasn't a reason not to do it now.
But during sometimes blistering questioning of the defense, Judge Richard Posner said Judge Coleman failed to thoroughly evaluate the FISA records herself before agreeing to open them up to the defense.
Another of the appeals court panelists, Judge Ilana Diamond Rovner, added that Coleman appeared to have "discarded" applicable FISA law and come up with her own justification for opening the records.
Rovner noted in a question for Ridgway that when Congress enacted the FISA law in the 1970s, it could have clearly indicated defense attorneys should never get access to the records. But it didn't do that, she said.
"Can you give me any scenario where disclosure (to the defense) would be necessary?" Rovner asked.
"It would be a rare circumstance," Ridgway, the assistant U.S. attorney, responded.
Another issue of secrecy arose unexpectedly after 30 minutes of arguments in open court when Posner announced the panel was now "going to have a secret hearing" on Daoud's case. He ordered spectators, journalists and the entire defense team to leave — though nearly two dozen U.S. prosecutors were allowed to stay.
Thomas Durkin, another one of Daoud's attorneys, criticized the order.
"This is a sad day for the justice system," he told reporters.
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