But Democrats on the Senate Judiciary Committee countered that legislation updating the 1978 law covering such monitoring — the Foreign Intelligence Surveillance Act (FISA) — is tilted too far in favor of Bush, since it would also award a secret court jurisdiction to determine whether the current program is legal.
They argue that updating the law is a secondary concern since the White House claims its ongoing surveillance operations in the war on terror are not bound by it.
Technological advances and a shift in adversaries from Cold War rivals to terrorists mean the FISA law is now behind the times, CIA Director Gen. Michael Hayden told the panel.
For starters, the existing law covers telephone and e-mail traffic that are routed through the United States, but which begin and end overseas.
As part of a deal with Bush to submit his warrantless wiretapping program for court review, the Republican-controlled committee is considering updating the FISA law. The administration monitors international calls and e-mails of Americans if terrorism is suspected.
"Congress did not anticipate the technological revolution that would bring us global high-speed fiber-optic networks, the Internet, e-mail and disposable cell phones," said Acting Assistant Attorney General Steven Bradbury.
But tinkering with the law brings into play the larger question of whether the administration is violating constitutional protections against illegal searches by permitting electronic spying in the United States without a judge-approved search warrant.
The administration has argued that the ongoing surveillance program, revealed by The New York Times in December, is exempt from the restrictions of the FISA law.
It argues that a 2002 law giving Bush authority to use military force against Saddam Hussein also gave him authority to conduct the warrantless wiretapping program without obtaining permission from a secret FISA court established by the 1978 law. Considerable controversy has followed, with Democrats and some Republicans arguing that the administration is openly breaking the law.
"Whether or not FISA is in need of fine-tuning is a legitimate consideration, but FISA's possible imperfections provide no excuse for the administration's flouting of existing law," said Sen. Patrick Leahy of Vermont, the top Democrat on the panel.
Judiciary Committee Chairman Arlen Specter, R-Pa., is pushing new legislation to give the secretive FISA court jurisdiction over whether the administration's domestic spying program is legal.
The measure comes as lawsuits have sprung up in other federal courts. The White House is battling them, arguing that they should be dropped because state secrets would be revealed if they are thoroughly argued.
"There has to be a balance to the value to security, contrasted with the intrusion into privacy, and that can only be determined by judicial review," Specter said. "And in a context where the president is demonstrably unwilling to have the program subjected to public view, it would have to be determined by the FISA court if it is to be ruled on constitutionally at all."
On Tuesday, a federal court threw out a lawsuit aimed at blocking AT&T Inc. from giving telephone records to the government for use in the war on terror on the grounds that information would be disclosed that would reveal too much about the government's intelligence programs to U.S. adversaries.
A similar lawsuit against AT&T in San Francisco is proceeding, however, though Specter said U.S. District Judge Vaughn Walker's ruling in that case expressed so many concerns about national secrets that it seems likely to be closed soon.
Specter's bill would also require the attorney general to provide the court with information on the program's legal basis, the government's efforts to protect Americans' identities and the process used to determine that the intercepted communications involved terrorism. It would also clarify that international calls that merely pass through terminals in the United States are not subject to the judicial process established under the law.