(Photo: AP)

He was indicted on Oct. 28, 2005. That same day, he resigned.

Libby's conversations with reporters about CIA operative Valerie Plame, wife of former ambassador Joseph Wilson, are at the heart of the case.

CBS News correspondent Peter Maer reported that until the CIA leak case, Libby had been a behind-the-scenes power player.

Libby was a man with administration clout. He had three titles: chief of staff and national security adviser to the vice president and assistant to the president. He was an early proponent of going to war in Iraq and, by all accounts, a zealous guardian of the administration's strategy there. He was reportedly very angry about criticism of the war by Joseph Wilson.

In a 2002 interview, Libby told Public Radio's "Dianne Rehm Show" about the relationship between reporters and confidential sources. "They believe there are people who will not come forward and tell you what they really think unless they can keep their identity confidential," Libby said. "Courts have recognized that privilege because they think it's a common sense notion."

Libby was considered Cheney's alter ego, a chief architect of the war with Iraq. A trial would give the public a rare glimpse into Cheney's influential role in the West Wing and his behind-the-scenes lobbying for war.