WASHINGTON -- The fallout from last week's criminal indictment in the CIA-leak case, and the potential political damage for Vice President Dick Cheney, will in some measure depend on the events of June 12, 2003.

According to the five-count federal indictment against I. Lewis "Scooter" Libby, that was the day Mr. Libby "was advised" by Mr. Cheney that former diplomat Joseph Wilson's wife worked in the counterproliferation division of the Central Intelligence Agency. On the same day, the Washington Post reported that an unidentified former ambassador had been sent on a special mission to Niger to investigate claims that Iraq had tried to buy uranium yellowcake from the African country.

 The unmasking one month later of Mr. Wilson's wife, covert operative Valerie Plame, in a newspaper article by columnist Robert Novak, triggered the investigation leading to Friday's indictment. Mr. Libby, who resigned as Mr. Cheney's chief of staff shortly afterward, is expected to be arraigned at the federal courthouse in Washington on Thursday, a court official said. He is expected to plead not guilty to the charges of perjury, false statements and obstruction of justice. Mr. Libby is looking to expand his legal team and has approached at least three attorneys in Washington with experience handling criminal cases, said an attorney familiar with the matter.

Mr. Libby's lawyer, Joseph Tate, didn't return a call seeking comment.

What happened on June 12, 2003, and the vice president's role that day, almost certainly would be explored in any trial that resulted from the charges against Mr. Libby. In the days before June 12, Mr. Libby repeatedly asked for and received information from the State Department and the CIA about Mr. Wilson's trip, according to the indictment. On June 11 and June 12, he was orally told by both a State Department official and a CIA officer that Mr. Wilson's wife worked at the CIA, though it is unclear if her name was said.

"On or about June 12," the indictment states, Mr. Cheney also told Mr. Libby the same information and Mr. Libby was given to understand that his boss heard this from the CIA.

The indictment doesn't allege that Mr. Cheney named Ms. Plame or encouraged Mr. Libby to discuss her employment with reporters. It is unclear whether others were involved in that discussion, or only the vice president and Mr. Libby. If Mr. Cheney told Mr. Libby about Ms. Plame's employment, it wouldn't be illegal, since both men were cleared to learn classified information, such as the identity of a covert CIA operative.

In the weeks thereafter, Mr. Libby -- usually known for his discretion -- discussed Mr. Wilson's trip and his wife, Ms. Plame, with reporters and administration officials.

"The conversation with Cheney would be the first link in the chain," says Stephen Hess, a former Nixon administration official now at George Washington University. "We haven't seen the end of this [matter] by any means -- in fact, we're at the very beginning."

Ms. Plame's identity was leaked at a time when the White House was feeling defensive about the Iraq war. Just weeks earlier, President Bush, wearing a flight suit and standing on an aircraft carrier before a "mission accomplished" banner, had declared that major fighting in Iraq was over. Even then, it was becoming clear that Iraq's ousted regime didn't possess unconventional weapons and that the war was going to prove more of a slog than some in the administration had expected.

In the indictment, special prosecutor Patrick Fitzgerald said Mr. Libby told a federal grand jury he had no idea who Ms. Plame was until he was told so by reporters. However, Mr. Libby knew early on about Ms. Plame, in part from his boss, Vice President Cheney.

These aren't the only meetings in which Mr. Libby may have discussed how to handle media queries about Ms. Plame. On July 7, the indictment says, he spoke to the president's press secretary about the fact that Mr. Wilson's wife worked at the CIA, and that this information wasn't widely known. On July 12, he discussed it again with members of the vice president's office while traveling with them aboard Air Force Two.

Mr. Hess says he believes Mr. Libby eventually may feel pressure to settle the case without a trial.

The White House confirmed yesterday that David Addington, the vice president's chief counsel, has been named to serve as his chief of staff. Mr. Libby's deputy, John Hannah, will become Mr. Cheney's assistant for national security affairs, the White House said in a news release.

Write to Christopher Cooper at christopher.cooper@wsj.com and Anne Marie Squeo at annemarie.squeo@wsj.com

Commentary:
Readers of this website already know what happened on June 12, 2003. For new readers, Walter Pincus wrote an article on that day using quotes from an unnamed ambassodor (Wilson). According to "TIME" the White House, NSC and State wanted to know everything they could about Wilson's trip "After Pincus"