The Main Players in the Lewis Libby Trial.

Lewis 'Scooter' Libby

Characteristically, the former vice-presidential aide has several different explanations for how he came by his nickname - either from his father, impressed by the energy and agility of his infant son, or from a comparison with a well-known New York Yankees baseball player.

Until his dramatic fall, Libby was one of the most powerful neocons in Washington, tutored at Yale by Paul Wolfowitz and brought by him to the Reagan state department in the 1980s. But for most of his life, Libby has been a lawyer and occasional novelist. One of his novels, The Apprentice, recounts tales of bestiality and paedophilia in early 20th century Japan. In the White House, he became so powerful and so close to the vice-president, he was known as "Dick Cheney's Dick Cheney".

Valerie Plame

The spy at the heart of the affair. As far as her neighbours in suburban Washington were concerned, she was a mundane civil servant and mother of twins. In fact she was an undercover CIA agent, given the job of trying to find evidence to back up White House claims about Iraqi WMD. Her cover was blown in July 2003 by administration officials briefing Washington journalists.

Joe Wilson

Plame's husband annoyed the White House enough to provoke the leak. He was a flamboyant and freewheeling ex-ambassador, who had once faced down Saddam Hussein when he was the last US envoy in Baghdad.

He was sent to Niger in February 2002 to chase up claims from vice-president Cheney's office that Iraq was trying to buy uranium in west Africa, but found the lead to be a dead end. He was shocked then to hear the claim repeated in president's Bush pre-war state of the union address in January 2003.

In July that year, he blew the whistle in a New York Times commentary entitled: "What I didn't find in Africa." Days later, journalists were being told by angry Bush administration officials that he had no qualifications to go on the Niger trip, other than having a wife who was well placed in the CIA.

Karl Rove

The Machiavelli in the court of George Bush came close to be being dragged into court along with Libby. He had also been telling journalists about Plame's identity, but unlike the lawyer, he belatedly admitted it, and avoided charges of perjury and obstruction of justice. The leak itself was not, in the end, considered a crime.

Robert Novak

The veteran Washington journalist who blew Plame's cover in July 2003. The trial exposed the cosy, incestuous world of information and spin trading among conservative columnists like Novak and administration insiders. Novak avoided jail by promptly handing his sources to investigators.