Original Article Eavesdropping inquiry may widen Congress set to look at new allegations Eric Lichtblau New York Times Dec. 25, 2005 12:00 AM WASHINGTON - Congressional officials said Saturday that they wanted to investigate the disclosure that the National Security Agency had gained access to some of the country's main telephone arteries to glean data on possible terrorists. "As far as congressional investigations are concerned, these new revelations can only multiply and intensify the growing list of questions and concerns about the warrantless surveillance of Americans," said Sen. Patrick Leahy of Vermont, the ranking Democrat on the Judiciary Committee. Members of the Judiciary Committee have indicated that they intend to conduct oversight hearings into the president's legal authority to order domestic eavesdropping on terrorist suspects without a warrant. But congressional officials said Saturday that they would probably seek to expand the review to include the disclosure that the security agency, using its access to giant phone "switches," had also traced and analyzed phone and Internet traffic in much larger volumes than what the Bush administration had acknowledged. Current and former government officials say the security agency, as part of its domestic-surveillance program, has gained the cooperation of some of the country's biggest telecommunications companies to get access to large volumes of international telephone and Internet traffic flowing in and out of the United States. The agency has traced and analyzed the traffic flow, looking at who is calling whom, where calls originate and end and other patterns, to gather clues on possible terrorist activities. In cases in which security agency supervisors believe they can show a link to al-Qaida, President Bush has authorized the agency to eavesdrop on the calls without a warrant within the United States, so long as one end of the phone or e-mail conversation takes place outside the country. The White House declined to comment Saturday on the security agency program or the use of data-mining, saying it would not discuss intelligence operations. Defenders of the program within the federal government say the security agency's broad analytical searches and data-mining, combined with actual eavesdropping, are an essential part of detecting and preventing terror attacks before they can occur. But civil rights and privacy advocates voiced concerns Saturday about the expanded role played by the security agency, which historically has been focused almost exclusively on foreign powers, in mining for data on American telephone lines.