This article was reported by Todd S. Purdum, David Johnston and Douglas Jehl and written by Mr. Purdum.
WASHINGTON, Nov. 16 - The disclosure that a current or former Bush administration official told Bob Woodward of The Washington Post more than two years ago that the wife of a prominent administration critic worked for the C.I.A. threatened Wednesday to prolong a politically damaging leak investigation that the White House had hoped would soon be contained.
The revelation left the special prosecutor, Patrick J. Fitzgerald, grappling with an unexpected new twist - one that he had not uncovered in an exhaustive inquiry - and gave lawyers for I. Lewis Libby Jr., Vice President Dick Cheney's former chief of staff and the only official charged with a crime, fresh evidence to support his defense.
Mr. Woodward's account of his surprise testimony to Mr. Fitzgerald - reported by The Post in Wednesday's issue and elaborated on in a first-person statement - now makes it apparent that he was the first journalist known to have learned the C.I.A. identity of Valerie Wilson, whose husband, former Ambassador Joseph C. Wilson IV, has sharply criticized the administration's rationale for war with Iraq.
He says that he was told in mid-June 2003 that Ms. Wilson worked as a C.I.A. weapons analyst, by an official who made an offhand reference that did not appear to indicate her identity was classified or secret.
Mr. Woodward said he provided sworn testimony to Mr. Fitzgerald on Monday, only after his original source went to the prosecutor to disclose their two-year-old conversation. But because Mr. Woodward said that source had still not authorized him to disclose his or her name, he set off a frantic new round of guessing about who that source might be and a wave of public denials by spokesmen for possible suspects.
A senior administration official said that neither President Bush himself, nor his chief of staff, Andrew H. Card Jr., nor his counselor, Dan Bartlett, was Mr. Woodward's source. So did spokesmen for former Secretary of State Colin L. Powell; the former director of central intelligence, George J. Tenet; and his deputy, John E. McLaughlin.
A lawyer for Karl Rove, the deputy White House chief of staff who has acknowledged conversations with reporters about the case and remains under investigation, said Mr. Rove was not Mr. Woodward's source.
Mr. Cheney did not join the parade of denials. A spokeswoman said he would have no comment on a continuing investigation. Several other officials could not be reached for comment.
Mr. Woodward, perhaps the nation's single most famous reporter, never wrote about the case, even after it became the most prominent story in Washington, although he made public statements dismissing its importance. He only informed The Post's executive editor, Leonard Downie Jr., of his knowledge last month, just before Mr. Fitzgerald indicted Mr. Libby on charges that he made false statements about his contacts with reporters and accused him of obstructing the investigation into whether the disclosure of Ms. Wilson's identity was a crime.
On Wednesday, Mr. Libby's lawyer, Theodore Wells, pronounced Mr. Woodward's revelation a "bombshell" that contradicted Mr. Fitzgerald's assertion that Mr. Libby was the first government official to discuss Ms. Wilson's C.I.A. connection with a journalist, Judith Miller, a former reporter for The New York Times, on June 23, 2003.
The latest revelation left Mr. Woodward, an assistant managing editor at The Post who operates with extraordinary latitude to produce best-selling books detailing the inner workings of the highest levels of government, in an unusual - and unusually uncomfortable role.
In a telephone interview, Mr. Woodward said he had apologized to Mr. Downie for not disclosing his own part in such a long-running story long ago and said he had kept a deliberately low profile to protect his sources. "The terms of engagement change when a reporter and reporters are being subpoenaed, agreeing to testify, being forced to testify, being jailed," Mr. Woodward said. "That's the new element in this. And what it did, it caused me to become even more secretive about sources, and to protect them. I couldn't do my job if I couldn't protect them. And to really make sure that I don't become part of this process, but not to be less aggressive in reporting the news."
It was not clear just what had prompted Mr. Woodward's original source to go to Mr. Fitzgerald, or whether that source had previously testified in the case. But Mr. Woodward was said to have begun making inquiries about the case before Mr. Libby's indictment, which may have been the catalyst.
If there are inconsistencies between Mr. Woodward's account and any earlier account by his source, Mr. Fitzgerald could be obliged to explore new legal implications.
The existence of Mr. Woodward's mysterious source came as a surprise to lawyers in the case, because it hinted that Mr. Fitzgerald had failed to learn a significant fact after two years of investigation, despite his reputation as a ferocious investigator who spent weeks digging out the smallest details before seeking indictments.
Randall Samborn, a spokesman for Mr. Fitzgerald, declined to comment on Mr. Woodward's statement. Mr. Libby was at the federal courthouse here on Wednesday, reviewing documents to aid in his defense. Lawyers involved in the case said that while the issues raised by Mr. Woodward's new account did not go to the heart of the perjury and obstruction charges against Mr. Libby, they could cast doubt on an underlying prosecution theme: that Mr. Libby was untruthful when he told the grand jury Ms. Wilson's C.I.A. identity was common knowledge among reporters.
In fact, only a small group of officials - at the White House, the State Department, and the Central Intelligence Agency - are believed to have known by early June 2003 about Ms. Wilson's ties to the C.I.A. They included Secretary Powell, Mr. Tenet, Mr. McLaughlin, Mr. Cheney, Mr. Libby; Marc Grossman, then the under secretary of state for political affairs; Carl Ford, then the head of the State Department's intelligence bureau; and Richard L. Armitage, then deputy secretary of state.
Mr. Wilson did not publicly identify himself until July 6 as the former ambassador who had made a trip to Niger in 2002 on behalf of the C.I.A. to investigate a claim that Iraq had tried to buy uranium there. Both The New York Times, in a May 6 column by Nicholas D. Kristof, and The Washington Post, in a front-page article on June 12 by Walter Pincus, had reported about the trip, but had not identified Mr. Wilson by name.
But former government officials have said that Mr. Pincus's inquiries at the White House, the C.I.A. and other agencies about Mr. Wilson's trip prompted Mr. Libby and other officials within the administration to try to learn more about the origins of the trip.
In his formal statement in The Post, Mr. Woodward said he had mentioned to Mr. Pincus in June 2003 that Ms. Wilson worked at the C.I.A. But Mr. Pincus, who has written that he first heard about Ms. Wilson from a senior administration official in July, said he did not recall that.
"The way he describes it, which is he walked by and said something about Wilson's wife being at C.I.A., I have absolutely no memory of it at all," Mr. Pincus said in a telephone interview. "And I think he may say that my reaction was 'What!' " like I was surprised. He now thinks I may never have heard him, and said, 'What?' "
Mr. Pincus did recall a later conversation with Mr. Woodward, in October 2003, after Mr. Pincus wrote about administration officials' efforts to discredit Mr. Wilson. He said Mr. Woodward stopped by his desk to tell Mr. Pincus that he "wasn't the only one who had been told," about Ms. Wilson's identity before it was publicly revealed in a syndicated column by Robert D. Novak on July 14, 2003. Mr. Pincus said Mr. Woodward "asked me to keep him out of my reporting, and I agreed to do it."
Mr. Pincus said he agreed not to pursue the question of whether anyone in the administration might have contacted Mr. Woodward because "he hadn't written a story."
He continued, "I was writing that they had talked to a group of people. I don't think I named everybody."
Mr. Fitzgerald's indictment of Mr. Libby provides some clues about the small number of people who were directly involved in exchanging information about the Wilsons. It says that Mr. Libby first sought information about Ambassador Wilson's trip from Mr. Grossman, on May 29, 2003. It says that Mr. Grossman directed Mr. Ford's intelligence bureau to prepare a report about Mr. Wilson and his trip to Niger, and briefed Mr. Libby about that report as it was being completed, telling him on June 11 or 12, 2003, that Mr. Wilson's wife worked at the C.I.A. and that State Department personnel were involved in the planning of the trip. Mr. Grossman declined to comment on Wednesday, and Mr. Ford did not reply to a telephone call and an e-mail message.
Mr. Libby also learned from a "a senior officer of the C.I.A." on or about June 12, 2003, that Mr. Wilson's wife worked at the C.I.A. and was believed to be responsible for sending Mr. Wilson on the trip, the indictment says.
The indictment says that it was Mr. Cheney who specifically first told Mr. Libby, on or about June 12, 2003, that Ms. Wilson worked in the counterproliferation division at the C.I.A., a fact that meant that she worked within the agency's clandestine service, where many employees are undercover. It says that Mr. Libby understood that Mr. Cheney had learned the information "from the C.I.A.," and people who have been officially briefed on the investigation say that notes taken by Mr. Libby at the time say that Mr. Cheney learned it from Mr. Tenet.
Others mentioned in the indictment as having discussed Mr. Wilson's trip with Mr. Libby in June or July 2003 include Eric Edelman, then Mr. Cheney's national security adviser; Catherine Martin, then his director of public affairs; Ari Fleischer, the former White House press secretary; Mr. Rove, Mr. Bush's political adviser; and David Addington, the counsel to the vice president. Other administration officials known to have been interviewed by investigators include Condoleezza Rice, who was then national security adviser and is now secretary of state; Stephen Hadley, then deputy national security adviser and now the national security adviser; Mr. Card; and Mr. Bartlett.
Mr. Woodward's statement could help Mr. Libby counter one of the main charges against him, that he lied to the grand jury about a conversation with Tim Russert, NBC's Washington bureau chief, in which Mr. Libby asserted that it was Mr. Russert who told him about Ms. Wilson. The lawyers said that they could say he merely misspoke, never intending to mislead the grand jury because he honestly believed he had heard about the C.I.A. officer as the subject of gossip in news media circles.
But some legal experts were skeptical that Mr. Woodward's disclosure would significantly alter the case against Mr. Libby.
"I don't think that in a technical legal sense it matters," said Rodney A. Smolla, dean of the law school at the University of Richmond and a specialist in media law. "It's neutral as to Libby because he has been indicted for perjury and for lying, and nothing in his account seems to sanitize those lies if in fact they turn out to be lies."
Other than Mr. Libby, the only administration official publicly known to have talked with reporters about Ms. Wilson's identity is Mr. Rove.
Other mysteries remain. It is still not known who first told Mr. Novak about Ms. Wilson. In addition, Mr. Pincus has never publicly disclosed the identity of an administration official he says told him on July 12, 2003, that Mr. Wilson's trip was "a boondoggle" by his wife. Mr. Pincus has said he testified about that exchange in 2004 after his source told prosecutors about it; Mr. Novak is also believed to have testified in the case, although he has not said so publicly.
Mr. Woodward wrote that he conducted three interviews related to the investigation, which were mainly background interviews for his 2004 book, "Plan of Attack," about the Iraq war. He said that he had confidentiality agreements with each of these sources, who signed written statements releasing him from his previous pledge of secrecy.
Mr. Woodward said that he testified about a second meeting on June 20, 2003, with a second administration official who was not identified by Mr. Woodward, but whom The Post identified on its Web site Wednesday as Mr. Card. Mr. Woodward wrote that he had a list of questions to the interview that included a line that said "Joe Wilson's wife." A tape of the interview contained no indication that the subject had come up.
A third conversation was conducted by phone with Mr. Libby on June 23, 2003. Mr. Woodward told him that he was sending 18 pages of questions intended for Mr. Cheney, including one that referred to "yellowcake," the uranium ore at the center of Mr. Wilson's fact-finding trip to Africa. "I testified that I have no recollection that Wilson or his wife was discussed, and I have no notes of the conversation."
In the telephone interview, Mr. Woodward said that his goal had been "the protection of a confidential source, and aggressive reporting, and they do go hand in hand."
