US: US vice-president Dick Cheney could be called to testify in the trial of his former chief of staff, Lewis "Scooter" Libby, who is charged with perjury in connection with the leaking of a CIA agent's identity.
Special prosecutor Patrick Fitzgerald told a Washington court in a written submission this week that Mr Cheney's state of mind was "directly relevant" to whether Mr Libby lied to investigators about his own leak role.
Mr Fitzgerald said the vice-president could also authenticate notes he jotted in the margins of a 2003 opinion column in the New York Times by former ambassador Joseph Wilson. In the article, Mr Wilson condemned the administration's claim that Saddam Hussein had arranged to buy nuclear materials from Niger. He said he had been sent on a CIA-sponsored mission to Niger in 2002 to authenticate the allegations and found them to be without substance.
Less than two weeks after the article appeared, conservative columnist Robert Novak revealed that Mr Wilson's wife, Valerie Plame, was a CIA agent.
Mr Libby claimed initially that he had first heard about Ms Plame's identity from journalists, but later admitted Mr Cheney had told him that she was a CIA agent. Mr Libby then admitted he had passed the information to reporters.
Testifying before a grand jury, Mr Libby said the vice-president was so upset about Mr Wilson's claims that they discussed them every day after they appeared.
"He was very keen to get the truth out," Mr Libby said, quoting Mr Cheney as saying, "Let's get everything out."
Noting that Mr Libby "shared the interests of his superior and was subject to his direction", Mr Fitzgerald said understanding Mr Cheney's state of mind at the time of the leak was essential.