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Two Democratic senators plan to attach to the welfare reauthorization bill being debated Tuesday an amendment that would require National Security Adviser Condoleezza Rice (search) to testify publicly and under oath before the panel investing pre-Sept. 11, 2001, anti-terror efforts.

Sens. Charles Schumer of New York and Edward Kennedy of Massachusetts say the amendment to the bill will be a resolution urging Rice to tell the world what she knows.

"We have delegated to that distinguished group of commission members the continuation of the essential fact-finding process begun by our own intelligence committee," Kennedy said Monday on the floor of the Senate.

"The public and the Congress should not stand for anything less than full and prompt (cooperation). For a national tragedy of these proportions, the buck stops at the White House. Three thousand people died on our shores and on their watch and there should not be the slightest question that any White House staff member asked by the commission to testify under oath and in public must do so," Kennedy said.

The National Commission on the Terrorist Attacks on the United States (search) is working to meet a July deadline to figure out where the intelligence broke down before the Sept. 11, 2001, terror attacks on New York and Washington.

The commission's profile spiked last week after Richard Clarke (search), former counterterrorism coordinator for Presidents Clinton and Bush, started a media tour to promote his recently published book in which he wrote that the Bush administration did not pay enough attention to the threat from Al Qaeda (search) before the terror attacks. Clarke then testified before the Sept. 11 panel in an open session.

Clarke also accused the president of looking for a link between the hijackings and Iraq even after he had been told that none existed. But Clarke's comments appear to contradict his own August 2002 briefing to a group of reporters in which he laid out exactly what the White House did to develop an antiterrorism policy in the administration's eight months before the attacks.

Rice told a news show on Sunday that the White House obviously was concerned with the "urgent" threat of terrorism, as evidenced by President Bush meeting with CIA Director George Tenet 46 times prior to Sept. 11. Rice also said the president had instructed Clarke and others to develop a strategy to protect the homeland.

She did acknowledge that the president did seek a link between Iraq and the attacks, but that he dismissed it when the evidence showed that Al Qaeda had conducted the terror.

Rice has already appeared for four hours in front of the Sept. 11 commission to answer questions in private about what the administration had been doing about terror threats. She has rejected testifying in public, arguing that she is prevented by executive privilege (search) from revealing confidential conversations.

Executive privilege excuses the president's principal advisers from discussing communications if doing so would adversely affect the operations of the executive branch.

"There is an important principle involved here: It is a long-standing principle that sitting national security advisers do not testify before the Congress," she told "60 Minutes" on Sunday night.

Rice has offered to speak with the commission a second time — again in private — in order to clear up "a number of mischaracterizations" Clarke made about pre-Sept. 11 antiterror planning. White House spokesman Scott McClellan said discussions about such a meeting are under way with the commission.

"Condi very much looks forward to meeting with the commission again and answering all their questions," he said.

McClellan refused to say whether commission and White House officials are considering a compromise, such as allowing Rice to testify privately but then publicly releasing her statements.

Al Felzenberg, a spokesman for the commission, said only the White House can make such a decision. He said there is no talk about publicly disclosing what Rice said during her Feb. 7 meeting with the panel.

Jonathan Turley, a law professor at George Washington University, said that the only person who can claim executive privilege is the president. He is the "one executive who can hold the privilege and waive it."

Turley said that means the president, who has a long-standing position on preserving privilege that dates back to his days as governor of Texas, is not permitting Rice to speak.

"It's part of that penumbra that surrounds the president," Turley said. Turley did add, however, that cases of privilege can be brought to the courts, which generally do not accept a generalized claim of privilege, particularly involving overriding cases before Congress or its ancillary bodies.

White House advisers rarely testify before Congress or congressionally appointed panels like the Sept. 11 commission, but some legal scholars say that once Rice spoke to the media about the attacks and the advice she gave to the president, she lost her claim to executive privilege.

"The whole idea of executive privilege is that the president's advisers should be able to give advice in confidence," said Herman Schwartz, a constitutional law professor at American University. "That means the advice should be kept confidential. But she's talked to everybody under the sun.

"What is the difference between appearing before the commission privately, telling them her story, and saying it publicly under oath? She can't have it both ways," he said.

Added Louis Fisher, a senior specialist on separation of powers at the Congressional Research Service (search) and author of the 2004 book "The Politics of Executive Privilege," Rice "has the same risk on TV of disclosing confidences when people ask her about what did you say to President Bush. The argument isn't persuasive."

But Charles Fried, a constitutional law professor at Harvard Law School, said unlike Cabinet secretaries, Rice is a presidential adviser who was not confirmed by the Senate. Therefore, she is not bound by the same demands from Congress.

"If the Bush administration caved, it would open the door to not only this president, but future presidents, Democrat and Republican, being forced" to have close advisers testify in non-criminal matters relating to confidential political advice, said Fried, a solicitor general under President Reagan.

Fried added that previous instances of White House staff testifying to commissions involved criminal prosecutions or closed-door testimony. Rice has argued that no previous testimony by White House staff has dealt with policy issues.

Weekly Standard Editor Fred Barnes said that the only explanation why the Sept. 11 commission would want Rice to testify publicly is to shine the spotlight back on itself.

"They talked to her, they talked to her for four hours. They know what she has to say, they know her answers," Barnes said. "So what do they need to have her come and testify in public for? Just so they can preen and look good."

Turley added that putting aside the "merits of Clarke's book," the trend of insiders to release tell-all stories about internal workings of the executive branch erodes confidence in the ability to assert privilege.

"That's not healthy when you're dealing with lives," he said.

The Associated Press contributed to this report.