Karl Rove, who was not charged by the grand jury in the C.I.A. leak case, leaving the White House Friday with an aide, Susan B. Ralston.

Patrick J. Fitzgerald, the special prosecutor from Chicago, arriving Friday, to much attention, at the United States Courthouse in Washington.

Patrick J. Fitzgerald speaking to reporters in Washington, D.C.

I. Lewis Libby Jr., chief of staff to the vice president, riding to work this morning.

WASHINGTON (By Todd S. Purdum, NYTimes) October 28, 2005 — The capital stopped in its tracks on Friday to watch a trim, plain, soft-spoken prosecutor whose voice it had barely heard in two years call the most important aide to the most powerful vice president in American history a liar. Politely, calmly, but firmly - and over and over again.

The prosecutor, Patrick J. Fitzgerald, brought no charges on the issue that prompted his investigation: whether someone in the government committed a crime by leaking the classified C.I.A. identity of the wife of one of the sharpest critics of the administration's rationale for war with Iraq. But he offered renewed evidence of that oldest of Washington axioms: the cover-up is always worse than the crime.

In an hour long, live television news conference, Mr. Fitzgerald said that Vice President Dick Cheney's chief of staff, I. Lewis Libby Jr., had repeatedly told F.B.I. agents, and later a federal grand jury, that he was "just passing gossip from one reporter to another at the end of a long chain of phone calls" about the identity of the agent, Valerie Wilson. "It would be a compelling story that would lead the F.B.I. to go away," Mr. Fitzgerald said. "If only it were true."

It was as if Mr. Fitzgerald had suddenly morphed from the ominous star of a long-running silent movie into a sympathetic echo of Kevin Costner in "The Untouchables." And Mr. Libby's sworn testimony that he had learned of Ms. Wilson's identity from reporters suddenly seemed to spring from the same confidence that they would never contradict him that led Bill Clinton to assume that Monica S. Lewinsky had not saved evidence of their affair.

"We didn't get the straight story," Mr. Fitzgerald said, explaining his hitherto secret investigation and sometimes inscrutable moves. "And we had to - had to - take action."

As Mr. Fitzgerald spoke from the Justice Department, the cable television networks showed only mute, miniature split-screen images of counter programmed live speeches by Mr. Bush at the White House and Mr. Cheney in Savannah, Ga. Mr. Bush had begun the day by leaving the jurisdiction, for a speech in Norfolk, Va., in which he thanked his audience "for the chance to get out of Washington."

He ended it with a terse, angry-looking expression of regret at Mr. Libby's resignation, standing on the South Lawn of the White House, just yards from the spot where Mr. Clinton spoke defiantly on the day of his impeachment. Mr. Bush then joined his failed Supreme Court nominee, Harriet E. Miers, for the helicopter flight to Camp David for the weekend.

Ms. Wilson's husband, Joseph C. Wilson IV, a former ambassador who cast doubt on the administration's prewar assertion that Iraq had tried to buy uranium from Niger, did not get his wish to see Mr. Bush's chief political aide, Karl Rove, "frog-marched" from the White House. Mr. Fitzgerald brought no charges against him. But the investigation is continuing, preventing the president from being able to put the matter behind him.

"This keeps it hanging over their heads," said one senior official from a past Republican White House, speaking on the condition of anonymity so as not to quarrel publicly with Mr. Bush. "He needs to start anew. Now is the time to start anew. But I see no sign that they're going to."

And Mr. Fitzgerald's unvarnished charges that Mr. Libby lied repeatedly about his knowledge of Ms. Wilson's role (when Mr. Cheney was one of those who told him most explicitly that she was involved in counter proliferation work at the C.I.A.) kept alive questions about whether the administration misled Congress and the public with its original rationale for a war with Iraq that this week logged its 2,000th fatality.

"This case is bigger than the leak of highly classified information," said Senator Harry Reid of Nevada, the Democratic leader. "It is about how the Bush White House manufactured and manipulated intelligence in order to bolster its case for the war in Iraq, and to discredit anyone who dared to challenge the president."

Because the case involves the intersection of politics and the press, the day sometimes had a hall-of-mirrors element. At one point, Mr. Cheney's onetime press secretary, Pete Williams of NBC News, asked Mr. Fitzgerald how the prosecutor could take the word of "three reporters" (including his current bureau chief and boss, Tim Russert) "versus the vice president's chief of staff," with whom Mr. Williams served in the Pentagon when Mr. Cheney was secretary of defense in the first Bush administration.

"What I'll say is, we're comfortable proceeding," Mr. Fitzgerald replied.

Mr. Fitzgerald several times took pains to note that Mr. Libby was entitled to the presumption of innocence. But the formal legal language of the indictment has an inescapably damning tone. It charges that Mr. Libby "did knowingly and corruptly endeavor to influence, obstruct and impede the due administration of justice," by "misleading and deceiving the grand jury as to when, and the manner and means by which, Libby acquired and subsequently disclosed to the media information concerning the employment of Valerie Wilson by the C.I.A."

The Wilson affair is not Watergate, and Mr. Libby's alleged misdeed may seem small potatoes compared with the work of the Nixon-era White House "plumbers."

But the chain of events that led to this indictment is not entirely unlike the one that prompted the Nixon White House to try to discredit Daniel Ellsberg, the former Pentagon analyst who provided reporters with the secret government history detailing the growth of American involvement in Vietnam that came to be known as the Pentagon Papers. In that case, as in this, a White House sought to cast doubt on a critic of its foreign policy, only to enmesh itself in far deeper political and legal trouble by trying to hush up its efforts.

Mr. Fitzgerald used a homey baseball metaphor to explain why he had charged Mr. Libby with deception and obstruction, despite his inability to find evidence of an underlying crime in exposing Ms. Wilson's identity. He likened the situation to the beaning of a batter in a baseball game, with his job as prosecutor to determine whether the pitcher meant to "throw it under his chin" or simply let a bad pitch get away. In the end, the prosecutor said of Mr. Libby, "if you're asking me what his motives were, I can't tell you."

For his part, Mr. Bush vowed to "remain wholly focused on the many issues and opportunities facing this country," and added: "I got a job to do." Mr. Libby issued a statement through his lawyer expressing confidence that he would be exonerated.

Meantime, the media and legal machinery of scandal, at once familiar and unsettling, grinds on. By nightfall, CNN was replaying clips from Jan. 22, 2001, of Mr. Cheney swearing in a roomful of fresh-faced White House aides, all of whom vowed to preserve, protect and defend the Constitution, under whose powers and protections Mr. Libby was indicted.