Jan. 24 (Bloomberg) -- The Bush administration's domestic spying effort is needed to prevent terrorist attacks in the U.S., Attorney General Alberto Gonzales said in seeking to counter criticism of the program.

Gonzales, speaking at Georgetown University's law school in Washington, argued that President George W. Bush had authority from Congress and the Constitution to set up the program. About 25 law students silently protested during the half-hour speech, turning their backs on Gonzales and holding up a sign saying: ``Those Who Would Sacrifice Liberty for Security Deserve Neither.''

Gonzales didn't acknowledge the students, several of whom put black pillowcases over their heads. The attorney general cited new threats by al-Qaeda leader Osama Bin Laden and said Bush would continue to authorize the eavesdropping to protect U.S. citizens.

``This administration has chosen to act now to prevent the next attack, rather than wait until it is too late,'' Gonzales said. ``It is hard to imagine a president who wouldn't elect to use these tools in defense of the American people. In fact, I think it would be irresponsible to do otherwise.''

Gonzales's speech continued a Bush administration offensive this week to defend and bolster support for the classified program, which allows National Security Agency monitoring of international phone calls and e-mails to or from the U.S. without the approval of a federal court. Bush said yesterday the eavesdropping is needed to look into the ``dark corners'' of the world where terrorists hide.

Lawsuits Filed

Two civil rights groups have filed suit over the surveillance program, and the non-partisan Congressional Research Service released a report this month saying the administration's justification for conducting the spying without a warrant ``does not seem to be as well-grounded'' as its legal rationale suggests.

The Senate Judiciary Committee has scheduled hearings for next month on the spying and whether it violates a 1978 federal law that set up a special court to authorize domestic surveillance for foreign intelligence purposes. Gonzales is slated to testify before the committee on the legal authority for the program.

Senator Patrick Leahy of Vermont, the panel's top Democrat, said today the explanations offered by Bush and Gonzales haven't changed his view that the program is illegal.

`Millions of Dollars'

``They are spending millions of dollars flying the president all around the country, trotting Attorney General Gonzales out to basically repeat before as many cameras as he can, the same talking points,'' Leahy said at a press conference. ``Nothing has come out that convinces me this is legal.''

Last week, the Justice Department sent members of Congress a 42-page analysis saying Bush has the legal authority to conduct the wiretapping under his constitutional role as commander-in- chief and under the resolution passed by Congress authorizing military force after the Sept. 11 attacks.

Today, Gonzales said that press reports on the still- classified program are ``in almost every case, in one way or another, misinformed, confusing or wrong.'' He said the media have caused concern about the breadth of the spying.

The program, Gonzales said, is ``narrowly focused'' and is only used to monitor communications of members or suspected members of al-Qaeda and other terrorist groups.

To contact the reporter on this story: Robert Schmidt in Washington at rschmidt5@bloomberg.net.

Last Updated: January 24, 2006 16:19 EST