By Dan Levine
SAN FRANCISCO (Reuters) - A U.S. appeals court grappled on Wednesday with a lawsuit challenging the Federal Bureau of Investigation's ability to force Internet and telecommunications firms to turn over customer records without revealing the government's demands.
A lower court judge in San Francisco previously ruled such gag orders were unconstitutional in a lawsuit filed by an undisclosed telecom company.
At a hearing on Wednesday, a three-judge 9th U.S. Circuit Court of Appeals panel in San Francisco weighed whether the First Amendment allowed recipients of so-called "national security letters" to discuss them.
Judge N.R. Smith, a George W. Bush nominee, asked whether the government should have a greater responsibility to lift the gag order on its own. That would ease the burden on telecom companies who currently have to go to court, he said.
"It seems to me, if I'm going to narrow this particular statute, that there should be some obligation on the part of the government to end the order," Smith said. "Why isn't there?"
Douglas Letter, an attorney for the U.S. Department of Justice, said the FBI does not have the resources to continuously review thousands of national security letters to determine if secrecy is still warranted.
"The bureau would not be able to function," Letter said.
Tech companies have sought to clarify their relationships with U.S. law enforcement and spying agencies, especially after revelations by former National Security Agency contractor Edward Snowden that outlined the depth of U.S. spying capabilities.
Twitter Inc (N:TWTR), for instance, sued the U.S. Department of Justice on Tuesday following months of fruitless negotiations over how much information the company could disclose about government surveillance.
In the case at the 9th Circuit, the plaintiff telecom company said the FBI's gag orders surrounding national security letters represent an "unprecedented grant of authority" and violate the First Amendment. Those letters seek customer information like billing records, not the content of individual messages.
The government calls such secrecy "vital" in national security cases because public disclosure could interfere with the probe or endanger someone's physical safety.
Tech companies including Google Inc (O:GOOGL), Microsoft Corp (O:MSFT) and Facebook Inc (O:FB) filed legal arguments against the government in the case.
The government may not "foist a gag order upon the involuntary recipient of an NSL," the companies wrote, "let alone prohibit the recipient from even reporting periodically the aggregate number of such demands that it receives."
Judge Sandra Ikuta, another George W. Bush nominee hearing arguments on Wednesday, suggested the law may not violate free speech because the government only sought secrecy for information it disclosed that impacts national security. It does not prohibit speech about information someone receives independently.
"This is not, 'I have this great idea. I've uncovered corruption, and government says, no, I may not speak about that," Ikuta said.
A ruling could come at any time.
(Reporting by Dan Levine; Editing by Cynthia Osterman)