Updated

The Sept. 11 attacks convinced Congress that the federal government needed enhanced legal and investigative powers to pursue terrorists.

Yet in the two years since passing the Patriot Act (search), lawmakers have grown uneasy over Attorney General John Ashcroft's use of the expanded surveillance and detention powers. Not only are they leery of his requests for even greater authority, they are moving to curtail some of the tools they granted in the law.

The House voted last month to prohibit the use of federal funds on "sneak and peek" searches that the law says the government can conduct in criminal investigations without the property owner's or resident's knowledge and with warrants delivered afterward.

"This is the first of a whole group of assaults that we're going to make on the Patriot Act," said Rep. Butch Otter (search) of Idaho, one of the few Republicans who voted against it two years ago. "It was built in one day, but we're going to have to tear it down piece by piece."

Ashcroft defends the law as "a long overdue measure to close gaping holes in the government's ability, responsibly and lawfully, to collect vital intelligence information on criminal terrorists." He plans a public defense, starting with a speech Tuesday in Washington.

He also is visiting Philadelphia, Cleveland, Detroit and more than a dozen other cities to promote the law's successes. Also on his agenda is trying to dispel "misconceptions," according to the Justice Department, about what the law allows law enforcement officials to do.

Justice Department officials are predicting dire consequences if Congress takes back the post-Sept. 11 powers.

For example, Otter's measure, if the Senate agrees, "could result in the intimidation of witnesses, destruction of evidence, flight from prosecution, physical injury, and even death," Assistant Attorney General William Moschella (search) wrote lawmakers.

The law is officially named the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act (search). It granted the government broad powers for searches, wiretaps, electronic and computer eavesdropping, and wide access to financial and other information held by individuals and businesses.

Concerned about possible abuses, lawmakers put a 2005 expiration date on many of the wiretapping and surveillance measures, including a provision that gives authorities access to records of what people check out from libraries or buy from bookstores.

But that date is not soon enough for some lawmakers and others.

"When the Patriot Act was passed, smoke was still coming out of the rubble of the Pentagon and the twin towers" of New York's World Trade Center, Otter said. "We rushed in order to provide some comfort to the people of the United States. It was a big mistake."

A diverse group of lawmakers has filed bills to roll back portions of the law. The members of Congress include Sens. Russ Feingold, D-Wis., the only senator to vote against the measure, and Lisa Murkowski, R-Alaska, and Reps. Bernie Sanders, I-Vt., Jerrold Nadler, D-N.Y., and Joseph Hoeffel, D-Pa.

And others are talking about doing the same. Republican Sen. Larry Craig of Idaho, normally a staunch supporter of the Bush administration and its policies, said on Wednesday Congress must monitor how the Patriot Act is being used, "and there may come a time, and it may be next year, that we need to pull it back."

Alaska, Vermont and Hawaii, and 142 local governments have passed measures opposing the act. The American Civil Liberties Union and the New York-based Center for Constitutional Rights have separately sued in federal court to challenge different parts of the law.

The Justice Department insists that much of the opposition stems from confusion about what it does and does not allow federal law enforcement officers to do.

Ashcroft has defended the libraries provision, saying subpoenas of business or library records are subject to greater scrutiny by judges under the anti-terrorism law than those issued under regular criminal investigations.

"There is misinformation, misunderstanding about the Patriot Act," Ashcroft said in a recent television interview. "The American people get it pretty well."

Ashcroft has even used some of the Democratic presidential contenders' own words to shore up support for the law, which broke down the traditional wall between FBI and intelligence agents.

Referring to Sen. John Edwards, D-N.C., Ashcroft said, "As Edwards explained, 'We simply cannot prevail in the battle against terrorism if the right hand of our government has no idea what the left hand is doing,' Ashcroft told a domestic preparedness conference last month.