The identity of intelligence officials who are thought to have passed information about covert CIA operative Valerie Plame Wilson to Vice President Dick Cheney's former chief of staff, I. Lewis "Scooter" Libby, surfaced in a federal court document filed Friday evening.

Separately, Libby's defense team has once again attempted to engage in a high-stakes gambit to devalue the nature of Plame Wilson's status and work with the CIA. The attorneys claim that Plame Wilson was not a very important figure at the CIA and that therefore no damage was done to national security by unmasking her identity.

"The prosecution has an interest in continuing to overstate the significance of Ms. Wilson's affiliation with the CIA," the court filing states.

However, in previous hearings, Special Prosecutor Patrick Fitzgerald has pointed out time and again that Plame Wilson's CIA status is not the issue. Rather it's Libby's repeated lies to the grand jury and the FBI.

"We are trying a perjury case," Fitzgerald said during a February 24 court hearing. "What I am going to say to the jury in opening and closing and rebuttal is that Mr. Libby knowingly lied about what he did.

"And the issue is whether he knowingly lied or not," Fitzgerald added. "And if there is information about actual damage, whatever was caused or not caused that isn't in his mind, it is not a defense. If she turned out to be a postal driver mistaken for a CIA employee, it's not a defense if you lie in a grand jury under oath about what you said and you told people I didn't know he had a wife. That is what this case is about.  It is about perjury, if he knowingly lied or not."

In Friday's filing, Libby's attorneys attempted to push the blame for the leak onto other officials at the CIA and the State Department and said these officials will likely be called to testify at next year's criminal trial. In doing so, the attorneys disclosed in the 39-page document the identities of four CIA employees who possibly provided their client with information about Plame Wilson's work for the CIA.

The individuals were previously identified by their job titles in the five-count indictment handed up by a grand jury in late October against Libby. In Friday's court filing, Libby's defense team argued that they should be entitled to receive additional evidence being used by the Special Prosecutor to prove Libby lied to the FBI and the grand jury when he was questioned about his role in the leak.

In describing the evidence and the prosecution witnesses it pertains to, Libby's attorneys revealed the names of previously unknown CIA officials who may have communicated Plame Wilson's classified CIA work to Libby. It is not a crime for the CIA to disseminate classified information to White House officials like Libby who have the security clearance to receive such intelligence.

What's interesting, however, is that one of the CIA officials named in the indictment as a possible source of information for Libby is Robert Grenier, 51, head of the agency's top counterterrorism office. Grenier was fired last month because he opposed using torture tactics against al-Qaeda suspects at secret detention facilities abroad, intelligence sources and news reports said.

"When al Qaeda struck the World Trade Center and the Pentagon on Sept. 11, 2001, Grenier was station chief in Islamabad, Pakistan," the Washington Post reported in February. "Among the agency's most experienced officers in southwest Asia, Grenier helped plan the covert campaign that preceded the U.S. military ouster of al Qaeda and its Taliban allies from Afghanistan."

Former CIA Director George Tenet promoted Grenier in 2002 to head up the Iraq Issues Group, a position created specifically to prepare for the March 2003 Iraq invasion.

"Grenier's predecessor at the Counterterrorism Center, who remains undercover, moved on to become chief of the National Clandestine Service, the successor to the CIA's directorate of operations," the Post report added.

In their court filing Friday, Libby's attorneys wrote that if not Grenier, it's possible that John McLaughlin may be the CIA official who provided Cheney's former chief of staff with information on Plame Wilson.

"On or about June 11, 2003, Libby was informed by a senior CIA officer [possibly Robert Grenier or John McLaughlin] that Wilson's wife was employed by the CIA and that the idea of sending him to Niger originated with her," Friday's court filing states. This passage is identical to the October indictment filed against Libby. However, the indictment did not include the names of the individuals, only their positions in government.

McLaughlin was deputy director of the CIA. He resigned from the agency in November 2004 over bureaucratic infighting.

Separately, the filing also reveals the identities of a few CIA briefers that Libby complained to in June 2003 for "selective leaking" of concerns the agency had with pre-war Iraq intelligence that Libby claimed made the White House and the vice president's office look bad.

Friday's filing also states that "On or about June 14, 2003, Libby met with a CIA briefer. During their conversation he expressed displeasure that CIA officials were making comments to reporters critical of the Vice President's office, and discussed with the briefer, among other things, 'Joe Wilson and his wife Valerie Wilson,' in the context of Wilson's trip to Niger." The indictment also quotes Mr. Libby as criticizing the CIA for "selective leaking" of various "intelligence matters." The filing states "We believe that the briefer referred to is Craig Schmall and that he will be a witness for the government at trial too. (However, it is also possible that the briefer referenced in this paragraph is Peter Clement or Matt Barrett.)." Clement has worked at the CIA for nearly 30 years. He was the director of intelligence for the agency and has published books on Soviet foreign policy, Russian domestic politics, and politics in Central Asia.