The bill, known as the USA Patriot Act, gives federal authorities much wider latitude in monitoring Internet usage and expands the way such data is shared among different agencies.
"Today, we take an essential step in defeating terrorism while protecting the constitutional rights of all Americans," Bush said during a signing ceremony. The House of Representatives passed the bill by a vote of 357-66 on Wednesday, and the Senate on Thursday approved the measure 98-1.
Attorney General John Ashcroft vowed Thursday to use the new powers to track down suspected terrorists relentlessly.
"If you overstay your visas even by one day, we will arrest you. If you violate a local law--we will hope that you will, and work to make sure that you are put in jail and be kept in custody as long as possible," he said in a speech to the nation's mayors about how the law would target suspected terrorists.
Civil libertarians say the measure was passed in haste following the Sept. 11 terrorist attacks. They are particularly concerned that the surveillance powers give law enforcement too much leeway to collect private information on people on the periphery of investigations.
"The attorney general is making a full-court press on the Internet. They want to do a lot of data mining and investigations on the Internet, and because they are looking for a needle in the haystack, they are going to conduct investigations that take them to the outer circle," said Jerry Berman, executive director for the Center for Democracy and Technology (CDT).
"The trouble with the bill is that it's very sweeping and it can apply not just to suspected terrorists but people and organizations that may be engaged in lawful actions," Berman said.
The new bill was enacted in response to terrorist attacks on the World Trade Center and the Pentagon, which have sparked the largest criminal investigation in U.S. history. The investigation immediately cast a spotlight on government surveillance powers, as Ashcroft championed the need for new "tools" to track down potential terrorists after the attacks. Part of the new legislation includes the expansion of Internet eavesdropping technology once known as Carnivore.
But civil rights advocates have consistently cautioned against expanding surveillance powers unnecessarily, arguing that there is little evidence that tougher surveillance laws could have prevented the tragedy.
In response to the new legislation, the American Civil Liberties Union vowed Friday that it would work with the Bush administration and law enforcement agencies to make sure civil liberties were not compromised as a result of the new bill.
"The passage of this broad legislation is by no means the end of the story," ACLU Executive Director Anthony D. Romero said in a statement. "We will now work with ACLU affiliates around the country to monitor its implementation."
Gregory T. Nojeim, Associate Director of the ACLU's Washington Office, added: "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 threats to national security by the Attorney General."
Specifically, the bill expands a "pen register" statute to include electronic communications and Internet usage. The pen register previously referred to law enforcement powers involving the tracing of telephone numbers called by suspected criminals. By including electronic communications, the statute now allows investigators to easily obtain wiretaps for activity on the Internet, which can mean the collection of information more private than IP addresses, which are roughly the Net's equivalent of phone numbers.
In addition, Internet service providers must make their services more wiretap friendly, giving law enforcement the ability to capture pen register information or allowing the installation of Carnivore technology.
Critics say there is not enough clarity about what information is collected through surveillance technology. Lawmakers maintain that Carnivore doesn't include information from the subject line of an e-mail, but it may collect data such as names and Web surfing habits. Another major concern is that such investigations are kept secret.
"We don't know the scope of what pen register information can be collected in the context of e-mail," said Mike Godwin, policy fellow at CDT. "But what we do know is that it ought to require more judicial review than it gets. Information collected is going to be more private than just e-mail."
One potential coup for civil rights advocates could be in a provision introduced by House Majority Leader Dick Armey. The provision requires a judge to oversee the Federal Bureau of Investigation's use of an e-mail wiretap, ensuring some checks and balances over the use of Carnivore. Law enforcement will be required to report back in 30 days to an authorizing judge on information that was collected online during the investigation.
"This would require the FBI to show what was collected, by whom, and who had access to it," said Armey spokesman Richard Diamond. "That information would be transferred under seal to the judge authorizing the use of Carnivore."
While some provisions in the bill will expire in 2006, powers governing Internet surveillance are not included in the "sunset clause."
"We will be watching, and Congress will be watching," Diamond said. "And in four years, when the DOJ asks for reauthorization of their powers, Congress will make sure (that) if any of those new powers were misused...they will be taken away."