WASHINGTON - New York Times reporter Judith Miller testified before a grand jury Friday, ending her silence in the investigation into whether White House officials leaked the name of a covert CIA operative, Valerie Plame.

Miller, free after 85 days in jail, spent more than three hours inside the federal courthouse in downtown Washington, most of it behind closed doors with a grand jury.

Miller arrived at about 8:30 a.m. at the courthouse as part of an agreement reached Thursday with Special Counsel Patrick Fitzgerald to disclose her conversations in July 2003 with Vice President Dick Cheney's chief of staff, I. Lewis "Scooter" Libby.

Miller said in a statement that her source — identified by the Times as Libby — had released her from her promise of confidentiality.

But Libby's lawyer said Friday he and his client had released Miller long ago to testify, and were surprised when Miller's lawyers again asked for a release in the last few weeks.

"We had signed a waiver more than a year ago," Attorney Joseph Tate said. "We didn't think this had anything to do with Scooter. I was under the impression from talking to (Miller attorney Floyd) Abrams that she was protecting a number of other sources."

Tate said Miller's lawyers called recently and said there was "a misunderstanding and Judy wanted to hear it straight from the horse's mouth" that Libby was releasing her to talk to the grand jury about their conversation.

Tate said his client did not know or hear about Plame's identity until it appeared in a newspaper column by Robert Novak. "Scooter did not know the name until he saw it in the Novak article," he said.

Miller went to the grand jury area Thursday morning accompanied by her attorneys Robert Bennett and Abrams and colleagues from the Times.

Until a few months ago, the White House maintained for nearly two years that Libby and presidential aide Karl Rove were not involved in leaking the identity of Valerie Plame, whose husband had publicly suggested that the Bush administration twisted intelligence in the runup to the war in Iraq.

The timing of the criticism by former Ambassador Joseph Wilson was devastating for the White House, which was already on the defensive because no weapons of mass destruction had been found in Iraq. The president's claims of such weapons were the main justification for going to war.

Libby met with Miller just two days after Wilson blasted the Bush administration in a Times op-ed piece.

Time magazine reporter Matthew Cooper has testified recently that Rove and Libby had spoken to him about Wilson's wife that same week in July 2003 when Miller spoke to Libby.

In October 2003, with the criminal investigation gaining speed, White House spokesman Scott McClellan said of Rove and Libby: "Those individuals assured me they were not involved in this" leaking of Plame's identity.

Miller has been in custody in Alexandria, Va., since July 6. A federal judge ordered her jailed for civil contempt of court when she refused to testify.

The disclosure of Plame's identity by syndicated columnist Robert Novak on July 14, 2003, triggered a criminal investigation that could still result in criminal charges against government officials.

"My source has now voluntarily and personally released me from my promise of confidentiality regarding our conversations relating to the Wilson-Plame matter," Miller said in a statement Thursday. Her newspaper identified Libby as the source, saying that Miller and Libby spoke in person on July 8, 2003, then talked by phone later that week.

Times publisher Arthur Sulzberger Jr. said that "as we have throughout this ordeal, we continue to support Judy Miller in the decision she has made. We are very pleased that she has finally received a direct and uncoerced waiver, both by phone and in writing, releasing her from any claim of confidentiality and enabling her to testify."

White House aides signed waivers earlier in the probe, but Miller wanted and received personal assurances that her source's waiver was voluntary.

Fitzgerald spokesman Randall Samborn declined to comment.

President Bush has given varying accounts of the circumstances under which he would fire leakers in the Plame probe.

In September 2003, Bush said "we'll take the appropriate action" and his spokesman said "they would no longer be in this administration." In June 2004, Bush reiterated the pledge, answering "yes" when asked if he would fire anyone in his administration who leaked Plame's name. In July, amid revelations that Rove and Libby had been involved in the leaks, Bush said that "if someone committed a crime" he would be fired.

The federal grand jury delving into the matter expires Oct. 28. Miller would have been freed at that time, but prosecutors could have pursued a criminal contempt of court charge against the reporter if she continued to defy Fitzgerald.

Of the reporters swept up in Fitzgerald's investigation, Miller is the only one to go to jail.

Novak apparently has cooperated with prosecutors, though neither he nor his lawyer has said so.

Novak's column in July 2003 said two senior administration officials told him Plame had suggested sending her husband to the African nation of Niger on behalf of the CIA to look into possible Iraqi purchases of uranium yellowcake.

Wilson's article in the Times, titled "What I Didn't Find In Africa," had stated it was highly doubtful that any such transaction had ever taken place.

Commentary:
Why did it take this long for Libby to release Miller? Was it because DeLay was indicted jut two days ago? Sure it was. Why didn't Bush force this bastard to release Miller when this investigation began?