"We're calling the vice president," attorney Ted Wells said in court. Wells represents defendant I. Lewis "Scooter" Libby, who is charged with perjury and obstruction.
Early last week, Special Prosecutor Patrick Fitzgerald said he did not expect the White House to resist if Cheney or other administration officials are called to testify in Libby's trial, expected to begin in January.
However, CBS News legal analyst Andrew Cohen says, "I just don't see this White House, and Cheney in particular, rolling over and allowing Libby's attorneys to force the VP to discuss delicate policy matters under oath in open court in Washington. At a minimum, you would think the White House would push an executive branch argument just for the sake of precedent."
Libby is accused of lying to investigators about what he told reporters regarding former CIA operative Valerie Plame. Plame's identity was leaked to reporters around the time that her husband, former ambassador Joseph Wilson, publicly criticized the Bush administration's prewar intelligence on Iraq.
Sitting presidents, including Bill Clinton and Gerald Ford, have testified in criminal cases, but presidential historians and separation-of-powers experts said they knew of no vice president who has done so. The first President George H.W. Bush was subpoenaed to testify an Iran-Contra trial. At the time, Mr. Bush was Reagan's vice president, but he was president by the time a judge ruled he did not need to testify.
In addition to Cheney, other government officials and journalists are expected to be key witnesses in the trial, which is scheduled to start next month.
Former New York Times reporter Judith Miller and NBC News Washington bureau chief Tim Russert are expected to be prosecution witnesses. Libby's lawyers said in court papers that several reporters will testify on Libby's behalf.
Two unidentified reporters may resist testifying, Libby's attorneys said, but they expect to resolve that issue before trial.
Libby also has sought a subpoena for the tape of Washington Post reporter Bob Woodward's interview with former Deputy Secretary of State Richard Armitage. Armitage has admitted he discussed Plame's job with Woodward in 2003 but said it was a passing, inadvertent comment.
If admitted into evidence, the tape could be played at trial. The tape has been turned over to prosecutors, and Libby's attorneys said they expect no objection to their subpoena.
Cheney, who would be the trial's most anticipated witness, has said he may be called to testify. If so, prosecutors could ask how the White House responded to Wilson's criticisms. Cheney was upset by Wilson's comments, Fitzgerald has said, and told Libby that Plame worked for the CIA.
That conversation is a key to Fitzgerald's perjury case. Libby testified that he learned about Plame's job from a reporter.
Cheney could also help prosecutors undermine Libby's defense that he was so preoccupied with national security matters, he forgot details about the less-important Plame issue. Prosecutors argue that Plame was a key concern of the vice president, and thus would have been important to Libby.
Cheney and Libby got to know each other when Cheney was defense secretary under the first President Bush. Libby has been extremely loyal to Cheney and, in return, had the vice president's unwavering trust.
By 2000, Libby was working as a top adviser to Cheney in the presidential campaign and then followed him to the White House. In the White House, he was known as "Cheney's Cheney" for being as trusted a problem solver for the vice president as Cheney was for the president.
Even after Libby's indictment, Cheney called him "one of the finest men I've ever known."