"Today, we take an essential step in defeating terrorists while protecting the constitutional rights of all Americans," Mr. Bush said at White House ceremony attended by Vice President Dick Cheney, lawmakers and uniformed law enforcement officials.
The legislation, while somewhat weakened from the administration's original proposal, expands the FBI's wiretapping and electronic surveillance authority and imposes stronger penalties for harboring or financing terrorists. It also expands the number of crimes considered terrorist acts and increases the punishment for committing them.
"This law will give intelligence and law enforcement officials new tools to fight a present danger," Mr. Bush said.
The Senate approved the measure, 98-1, Thursday, a day after the legislation cleared the House, 357-66. The only dissenting Senate vote was cast by Sen. Russ Feingold, a Wisconsin Democrat.
Attorney General John Ashcroft said that as soon as the bill is signed, he would direct all federal prosecutors and FBI agents to begin using their increased powers immediately.
"Upon the president's signature, I will direct investigators and prosecutors to begin immediately seeking court orders to intercept communications related to an expanded list of crimes under the legislation," he said Thursday.
Major legislation often takes several months if not years to be approved. But this bill roared through Congress in less than six weeks.
Click here for a look at the 107th U.S. Congress.
But the Senate Judiciary Committee chairman, Sen. Patrick Leahy, D-Vt., said negotiators have placed safeguards on the legislation, like a four-year expiration date on the wiretapping and electronic surveillance portion, court permission before snooping into suspects' formerly private educational records and court oversight over the FBI's use of a powerful e-mail wiretap system.
Explicit and implicit safeguards in this legislation ought to minimize, if not absolutely erase, any excesses by cops or prosecutors, reports CBSNews.com Legal Analyst Andrew Cohen.
There's the sunset provision, and the federal judiciary is going to interpret all of this within Constitutional guidelines. Ad there are practical disincentives for the cops to go after people who aren't serious domestic terrorist threats.
"We were able to find what I think is the appropriate balance between protecting civil liberties, privacy and ensuring that law enforcement has the tools to do what it must," said Senate Majority Leader Thomas Daschle, D-S.D., said.
Highlights of the legislation include:
However, human rights and privacy advocates contend many problems remain in the final compromise.
"These new and unchecked powers could be used against American citizens who are not under criminal investigation, immigrants who are here within our borders legally, and also against those whose First Amendment activities are deemed to be a threat to national security by the attorney general," an American Civil Liberties Union letter says.
One of the most contentious portions of Mr. Bush's proposal would have allowed the attorney general to detain indefinitely until deportation any immigrant suspected of terrorism. House and Senate negotiators placed safeguards on that proposal by forcing to the attorney general to start deportation procedures immediately, charge the person with a crime or release the foreigner in seven days.
Some human rights advocates want it changed even more so that immigrants would not have to stay in jail while their cases go through the deportation process.
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