The legal maneuvering in the obstruction-of-justice case against a former White House aide, I. Lewis Libby, inched closer to President Bush yesterday as defense lawyers signaled that the president’s involvement in the campaign to counter an irksome war critic will be an issue at Mr. Libby’s trial.

In a 26-page brief filed in federal court in Washington late last night, Mr. Libby’s attorneys pressed their demands that the government be forced to hand over a wide array of documents that the lawyers contend are relevant to Mr. Libby’s defense, including records from the White House, the CIA, and the State Department.

Mr. Libby’s filing lacked the drama of last week’s written salvo from prosecutors, which triggered what the defense team called “an avalanche of media interest.” The prosecution brief, first reported by The New York Sun, disclosed that Mr. Bush allegedly sidestepped established declassification procedures by authorizing Vice President Cheney and his then-chief of staff, Mr. Libby, to give to the press sensitive data from a National Intelligence Estimate on Iraq.

Mr. Libby’s legal team did their best yesterday to capitalize on the furor over the claim that Mr. Bush played a role in a chain of events that, according to prosecutors, culminated in Mr. Libby exposing the identity of a CIA officer, Valerie Plame.

The special prosecutor, Patrick Fitzgerald, has argued repeatedly that because Mr. Libby is not charged with leaking Ms. Plame’s name, he should not be entitled to wide-ranging access to documents detailing how the Bush Administration sought to rebut damaging allegations made by Ms. Plame’s husband, Joseph Wilson, that Mr. Bush misled the public about Iraq’s nuclear procurement efforts. Mr. Libby resigned last year after being indicted on charges of obstruction of justice, perjury, and making false statements to investigators.

The defense lawyers, led by Theodore Wells Jr. of Manhattan and William Jeffress Jr. of Washington, argued in the latest filing that while prosecutors publicly set forth a detailed narrative about the release of data from the intelligence estimate, the government is resisting the defense’s efforts to get documents that might illuminate why and how that information was released.

“The prosecution is trying to have it both ways,” the defense team complained. “The government has effectively conceded that the case extends far beyond Mr. Libby, but refuses to provide defendant with discovery that reflects that fact.”

Defense attorneys stopped short of saying they wanted to subpoena Mr. Bush or seek direct testimony from him in a deposition or written statement. Any of those moves could provoke a high-stakes legal confrontation over executive privilege.

However, the lawyers made clear that the president could be dragged into the case if the prosecution proceeds with the line of argument it set forth last week.

“The government’s discussion of the NIE indicates that at trial all aspects of the government’s response to Mr. Wilson will be relevant—including any actions taken by the president,” the defense lawyers wrote. They said they were entitled to present testimony showing Mr. Libby’s actions “were authorized at the highest levels of the Executive Branch.” The attorneys also insisted they be allowed to explore whether, as prosecutors suggested, Mr. Libby had reason to fear he would be fired if his alleged role in leaking Ms. Plame’s identity came to light.

“Based on the government’s articulated motive theory, the defense is also entitled to investigate the administration’s response to the leak, such as any alleged threats by the president to fire officials who were involved. For example, if documents indicate that notwithstanding the president’s public statements about the leak investigation, Mr. Libby had no reason to fear losing his job, the defense is entitled to the production of such documents,” the defense team argued.

It was not clear whether the defense lawyers were arguing that Mr. Bush was duplicitous in his vows to fire anyone who leaked classified information about Ms. Plame or that Mr. Libby’s conduct was so far beyond reproach that he had no reason to be concerned about Mr. Bush’s pledge.

Yesterday’s filing also indicates that Mr. Libby’s trial, set for January 2007, could also expose deep rifts between the White House and the CIA. Defense lawyers said they plan to call the former director of central intelligence, George Tenet. He and other CIA employees may be biased against Mr. Libby because of previous clashes with the agency, the attorneys said. Mr. Libby’s attorneys have urged the judge in the case, Reggie Walton, to order the CIA to turn over the so-called referral documents that led to Mr. Fitzgerald’s probe. The prosecutor and the agency have refused to release those records and have claimed they are legally privileged.

On Tuesday, Mr. Fitzgerald corrected the brief he filed last week to withdraw an allegation that Messrs. Libby and Cheney deliberately told a New York Times reporter, Judith Miller, that a statement in the intelligence estimate about Iraq—that the country was “vigorously trying to procure” uranium—represented a consensus finding of the intelligence community, when it did not. The allegation of a deliberate distortion was prominently featured in news reports in the New York Times, the Washington Post, and elsewhere. Some of those outlets have corrected their reports in light of Mr. Fitzgerald’s letter to the court conceding the error.

“There is no basis for the media reports that accused Mr. Libby of misrepresenting the key judgments of the NIE to Ms. Miller,” the defense team said in its new brief.

While Mr. Fitzgerald Mr. Libby’s lawyers also argued that the former White House official “responded in good faith on the merits to Mr. Wilson’s allegations.” The attorneys said “contemporaneous documents reflect the points that Mr. Libby was to make to reporters, and those documents do not contain any information about Wilson’s wife.”

In a highly semantic point, the defense lawyers also denied that there is evidence that Mr. Libby “told any reporter” that Mr. Wilson’s wife, Ms. Plame, sent Mr. Wilson on a CIA-backed trip to Niger to investigate alleged Iraqi nuclear procurement. A Time magazine reporter, Matthew Cooper, told a grand jury that Mr. Libby replied to a question by saying he had heard that Ms. Plame sent her husband on the trip. However, the defense lawyers argue that the comment, which Mr. Cooper treated as confirmation, did not amount to telling a reporter about Ms. Plame’s alleged involvement in arranging the trip.