By Carol D. Leonnig
Washington Post Staff Writer
Saturday, January 7, 2006; A01

A report by Congress's research arm concluded yesterday that the administration's justification for the warrantless eavesdropping authorized by President Bush conflicts with existing law and hinges on weak legal arguments.

The Congressional Research Service's report rebuts the central assertions made recently by Bush and Attorney General Alberto R. Gonzales about the president's authority to order secret intercepts of telephone and e-mail exchanges between people inside the United States and their contacts abroad.

The findings, the first nonpartisan assessment of the program's legality to date, prompted Democratic lawmakers and civil liberties advocates to repeat calls yesterday for Congress to conduct hearings on the monitoring program and attempt to halt it.

The 44-page report said that Bush probably cannot claim the broad presidential powers he has relied upon as authority to order the secret monitoring of calls made by U.S. citizens since the fall of 2001. Congress expressly intended for the government to seek warrants from a special Foreign Intelligence Surveillance Court before engaging in such surveillance when it passed legislation creating the court in 1978, the CRS report said.

The report also concluded that Bush's assertion that Congress authorized such eavesdropping to detect and fight terrorists does not appear to be supported by the special resolution that Congress approved after the Sept. 11, 2001, terrorist attacks, which focused on authorizing the president to use military force.

"It appears unlikely that a court would hold that Congress has expressly or impliedly authorized the NSA electronic surveillance operations here," the authors of the CRS report wrote. The administration's legal justification "does not seem to be . . . well-grounded," they said.

Sen. Arlen Specter (R-Pa.), chairman of the Senate Judiciary Committee, has pledged to hold hearings on the program, which was first revealed in news accounts last month, and the judges of the FISA court have demanded a classified briefing about the program, which is scheduled for Monday.

"This report contradicts the president's claim that his spying on Americans was legal," said Sen. Frank Lautenberg (D-N.J.), one of the lawmakers who asked the CRS to research the issue. "It looks like the president's wiretapping was not only illegal, but also ensnared innocent Americans who did nothing more than place a phone call."

Justice Department spokesman Brian Roehrkasse said the president and the administration believe the program is on firm legal footing. "The national security activities described by the president were conducted in accord with the law and provide a critical tool in the war on terror that saves lives and protects civil liberties at the same time," he said. A spokesman for the National Security Agency was not available for a comment yesterday.

Other administration officials, who spoke on the condition of anonymity, said the CRS reached some erroneous legal conclusions, erring on the side of a narrow interpretation of what constitutes military force and when the president can exercise his war powers.

Bush has said that he has broad powers in times of war and must exercise them to target not only "enemies across the world" but also "terrorists here at home." The administration has argued, starting in 2002 briefs to the FISA court, that the "war on terror" is global and indefinite, effectively removing the limits of wartime authority -- traditionally the times and places of imminent or actual battle.

Some law professors have been skeptical of the president's assertions, and several said yesterday that the report's conclusions were expected. "Ultimately, the administration's position is not persuasive," said Carl W. Tobias, a University of Richmond law professor and an expert on constitutional law. "Congress has made it pretty clear it has legislated pretty comprehensively on this issue with FISA," he said, referring to the Foreign Intelligence Surveillance Act. "And there begins to be a pattern of unilateral executive decision making. Time and again, there's the executive acting alone without consulting the courts or Congress."

Marc Rotenberg, executive director of the Electronic Privacy Information Center, said the report makes it clear that Congress has exerted power over domestic surveillance. He urged Congress to address what he called the president's abuse of citizens' privacy rights and the larger issue of presidential power.

"These are absolutely central questions in American government: What exactly are the authorities vested in the president, and is he complying with the law?" Rotenberg said.

The report includes 1970s-era quotations from congressional committees that were then uncovering years of domestic spying abuses by J. Edgar Hoover's FBI against those suspected of communist sympathies, American Indians, Black Panthers and other activists. Lawmakers were very disturbed at how routinely FBI agents had listened in on U.S. citizens' phone calls without following any formal procedures. As they drafted FISA and created its court, the lawmakers warned then that only strong legislation, debated in public, could stop future administrations from eavesdropping.

"This evidence alone should demonstrate the inappropriateness of relying solely on executive branch discretion to safeguard civil liberties," they wrote. The lawmakers noted that Congress's intelligence committees could provide some checks and balances to protect privacy rights but that their power was limited in the face of an administration arguing that intelligence decisions must remain top secret.