A closed-door hearing beginning Wednesday will deal with a crucial issue in the trial of a former White House aide: whether President Bush's daily terrorism briefings and other sensitive documents should be disclosed in the CIA leak case.

The hearing, which could last several days, will help establish what classified information is relevant to the case against Vice President Dick Cheney's former chief of staff, I. Lewis "Scooter" Libby.

He is accused of perjury, obstruction and lying to the FBI about his conversations in 2003 with reporters regarding CIA operative Valerie Plame.

Libby wants to use the daily intelligence briefings and terrorism threat assessments as evidence to show he had important things on his mind and honestly didn't remember details about his conversations with reporters.

Prosecutors have said Libby is trying to sabotage the case by requesting so much classified information that the government will be forced to withhold it and let the case be dismissed. It's a legal tactic known as "graymail."

Special Prosecutor Patrick Fitzgerald argued in court papers filed late Monday that the intelligence briefings fall outside the rules of evidence and should not be allowed as evidence.

Fitzgerald was less opposed to Libby's request for records regarding former Ambassador Joseph Wilson's trip to Niger, saying they could be considered on a case-by-case basis. Wilson, Plame's husband, discounted reports that Saddam Hussein sought to buy uranium from the African country -- a claim Bush later included in his State of the Union address.

After the hearing, U.S. District Judge Reggie B. Walton will decide what documents should be allowed as evidence. He will then hold a second hearing, which also could take days, to decide how the documents should be blacked out or summarized to protect national security.

If, after those hearings, government officials still believe national security would be jeopardized, they can refuse to release the classified information. That could lead to the case being dismissed before trial starts in January.