NSA Spying Part of Broader Effort

"If you think about it technically, it is pretty clear that the NSA desk that does communications intercepts is separate from the desk that does data mining of call records," said Kim Taipale, executive director of the Center for Advanced Studies in Science and Technology Policy, a New York-based nonprofit group. "Those are separate processes, and to think of them as separate programs is not a stretch."

On the other hand, the activities were authorized under a single presidential order and were all part of an NSA effort to gather communications about suspected terrorists after the Sept. 11 attacks. That helps explain why many Democratic lawmakers and administration officials -- including FBI Director Robert S. Mueller III -- viewed the wiretapping as part of a larger NSA program, rather than a separate effort, as Gonzales's testimony has suggested.

"Both sides have a legitimate case, if you want to be legalist about it," Taipale said.

The 45-day reauthorization of a single presidential order was probably a "bureaucratic convenience" that eliminated the need to issue multiple authorizations, he added.

Kate Martin, executive director of the Center for National Security Studies, said the new disclosures show that Gonzales and other administration officials have "repeatedly misled the Congress and the American public" about the extent of NSA surveillance efforts.

"They have repeatedly tried to give the false impression that the surveillance was narrow and justified," Martin said. "Why did it take accusations of perjury before the DNI disclosed that there is indeed other, presumably broader and more questionable, surveillance?"

Charles E. Schumer (N.Y.), who was among a group of four Democratic senators who called last week for a perjury investigation of Gonzales, said: "The question of whether Attorney General Gonzales perjured himself looms as large now as it did before this letter.

"This letter is no vindication of the attorney general," he said.

Staff writer Joby Warrick and staff researcher Madonna Lebling contributed to this report.