In the sixth and seventh seasons, "The West Wing" explores a leak of top-secret information by a senior staffer at the White House. This leak has been compared to the events surrounding the Valerie Plame affair. In the storyline, the International Space Station is damaged and can no longer produce oxygen for the astronauts to breathe. With no other methods of rescue available, the president is reminded of the existence of a top-secret military space shuttle. Following the president's inaction, the shuttle story is leaked to a White House reporter, Greg Brock (analogous to Judith Miller), who prints the story in "The New York Times". Brock will not reveal his source and goes to jail for failing to do so, as did Miller. In order to stop the investigation, in which authorities suspect Chief of Staff C.J. Cregg, Toby Ziegler admits leaking the information, and the President is forced to dismiss him. In comparison, the Plame affair resulted in the arrest and conviction of Lewis Libby, the vice president's chief of staff. However, Libby was convicted of perjury in testimony to a grand jury. No one was convicted for "blowing the cover" of Plame. (Richard Armitage, an official in the Bush State Department, acknowledged leaking information about Plame to reporters but was never charged with a crime.) Libby's two and a half year prison sentence was later commuted by President Bush, though the other facet of his sentence ($250,000 fine) stands until Libby's appeals were to be considered.