A U.S. appeals court in San Francisco left a sealed document out of a case about alleged illegal surveillance by the federal government, but said the subject of the case itself is not secret because the government has discussed the program.

In the case of Al-Haramain Islamic Foundation v. Bush, an Islamic charity sued the government, alleging it illegally spied on the group. The case is one of several involving an alleged warrantless surveillance program launched by the Bush administration in the wake of the Sept. 11 terrorist attacks. An appeal in another such case, Hepting v. AT&T, was heard alongside the Al-Haramain case on Aug. 15, but the two were separated Friday when the court released its opinion.

The Department of Justice argued that the suit had to be thrown out because its very subject, the alleged surveillance program, was a state secret. The three-judge panel at the Ninth Circuit rejected that argument, saying the government had made limited statements about the program on several occasions. But it agreed with the government that the key document in the case was secret. Al-Haramain's lawyers have said they need the document to establish their case, and the government has argued it can't be introduced in the case, according to the opinion of Judge M. Margaret McKeown on Friday. Al-Haramain saw the document by accident at one time.

The judges sent the case back to the U.S. District Court for the Northern District of California to determine whether a law that regulates wiretapping without a warrant, the Foreign Intelligence Surveillance Act (FISA), overshadows the state secrets privilege the government wants to use. If the lower court decides it does, then a court might be able to look at the secret document behind closed doors and determine whether the wiretapping was illegal, said Kurt Opsahl, a senior staff attorney at the Electronic Frontier Foundation. EFF is representing the plaintiff in the Hepting v. AT&T case.

EFF believes the lower court's decision was well-reasoned and was disappointed to see the Ninth Circuit partly knock it down, Opsahl said. EFF has argued FISA pre-empts the state secrets privilege and hopes the lower court comes to that conclusion in this case, he said.

In the Hepting case, a class action on behalf of AT&T customers, the EFF alleges AT&T cooperated with the National Security Agency to conduct surveillance of millions of customers' communications illegally, violating the customers' privacy.