WASHINGTON -- President Bush used his year-end news conference yesterday to resume his public relations offensive against his critics, saying he wants the Justice Department to find out who committed the ''shameful act" of leaking word that he secretly approved a special program to spy on US citizens, and blasting senators who have blocked the renewal of the Patriot Act.
Meeting with reporters at the White House, Bush said he has the power as commander in chief to repeatedly authorize the National Security Agency to listen in on private domestic phone calls to crack terrorism cases, and that program needs secrecy to avoid tipping off suspected terrorists. ''My personal opinion is, it was a shameful act for someone to disclose this very important program in a time of war. The fact that we're discussing this program is helping the enemy."
Some Democrats and Republicans, however, want public hearings to determine if the eavesdropping program, conducted without a warrant or a judge's permission, violates the Constitution.
But Bush said his legal staff researched the issue and found he had the authority to give the NSA permission to conduct wiretaps and surveillance without warrants -- and he expects federal agents to look into who leaked word about the program, first reported on Friday by The New York Times.
The program targeted people in the United States who were communicating with people in other countries; the NSA chiefly monitors communications by foreign agents overseas and in the United States.
Bush also had some tough talk for senators who are using a filibuster to keep the Patriot Act -- which the White House considers a crucial law-enforcement tool against terrorism -- from being renewed until concerns about civil liberties are addressed.
If the filibuster continues, Bush said, ''I want senators from New York or Los Angeles or Las Vegas to explain why these cities are safer" without the act.
His remark seemed to target three Senate Democrats who helped block the measure: Hillary Clinton of New York, Barbara Boxer of California, and Harry Reid of Nevada, minority leader.
Bush did not mention that four Republican senators have joined the Democrats in sidetracking the Patriot Act: Chuck Hagel of Nebraska, John Sununu of New Hampshire, Larry Craig of Idaho, and Lisa Murkowski of Alaska.
Bush took particular aim at Reid, noting that ''the Senate Democratic leader boasted to a group of political supporters that the Senate Democrats had 'killed the Patriot Act.' "
Reid said yesterday that he wanted to improve the act, which gives authorities wide latitude in pursuing investigations of people suspected of terrorist ties.
''Let's be clear about who's killing the Patriot Act -- President Bush and the Republican leadership," Reid said. ''Twice last week, a bipartisan group of senators tried to move forward on a three-month extension, but instead of joining us, the president and the Republican leadership decided they would rather see the bill expire."
At the news conference, Bush bristled when asked if his actions would create a ''more or less permanent expansion of the unchecked power" of the presidency.
''I disagree with your assertion of 'unchecked power,' " Bush said. ''Hold on a second, please. There is the check of people being sworn to uphold the law, for starters. There is oversight. We're talking to Congress all the time, and on this program, to suggest there's unchecked power is not listening to what I'm telling you. I'm telling you, we have briefed the United States Congress on this program a dozen times."
But Reid said yesterday that he learned about the NSA program -- launched after the Sept. 11, 2001, terrorist attacks and renewed by Bush more than 30 times since -- in a brief conversation earlier this year.
Reid surmised that 96 out of 100 senators learned about it from The New York Times.