The Bush administration will do everything possible to ensure the government has the tools to fight terrorists before the next president takes office, while protecting people's privacy, Attorney General Michael Mukasey said Wednesday.

Civil rights activists warn against the FBI using terrorist profiles that potentially single out Muslims, Arabs and other racial and ethnic groups instead of relying on evidence of wrongdoing as the basis for investigating Americans.

The nation's top law enforcer told the Senate Judiciary Committee that he would safeguard privacy rights. But, he said, it also is "important that we do everything we can to give our national security professionals — who will be confronting the al-Qaida threat well after this administration is over — the tools they need to keep us safe."

Mukasey said he is considering changes so FBI agents have "clear and consistent rules for conducting investigations while maintaining vital civil liberties protections."

Asked if the policy changes would let the FBI investigate Americans solely because of their race or ethnicity, Mukasey bluntly answered: "No."

When pressed by Sen. Russ Feingold, D-Wis., however, on whether people might be investigated based on their ethnicity, travel habits and whether they own a gun, Mukasey declined to answer directly.

He said, "The nature of evidence gathered and the way that it's gathered will be subject to review."

Critics say the still-tentative policy would open the door to racial profiling. Department officials, however, say the changes would help investigators root out terrorists before they strike.

Committee Chairman Patrick Leahy, D-Vt., said President Bush has improperly used the department to spy on people in the United States, has authorized the torture of suspected terrorists and has undercut environmental laws. "This administration makes the Watergate looks like child's play," Leahy said.

Added the committee's top Republican, Sen. Arlen Specter of Pennsylvania: "Since 9/11, I believe historians will look back at this period as the greatest expansion of executive authority that has gone unchecked by the Congress."

The proposed Justice policy, first reported last week by The Associated Press, would let FBI agents open preliminary terrorism investigations after mining public records and intelligence to build a profile of traits that, taken together, are deemed suspicious. Factors that could make a U.S. citizen or resident the subject of an investigation include travel to regions of the world known for terrorist activity, access to weapons or military training and someone's race or ethnicity.

The department has declined to discuss details of the proposed policy because it is not yet final. On Wednesday, Justice spokesman Brian Roehrkasse said, "At the end of the day, the FBI is not going to open an investigation simply on the basis of race, ethnicity, or religion."

Caroline Fredrickson of the American Civil Liberties Union said Mukasey should have to spell out the changes to ensure there is no discrimination against racial and ethnic groups.

"We cannot let the Department of Justice selectively apply the presumption of innocence," Fredrickson said in a statement. "Treating all Arabs and Muslims as suspects is not just illegal, it is also an ineffective and counterproductive way to conduct terrorism investigations."