Among the many questions surrounding the investigation into who in the Bush administration leaked the name of an undercover CIA officer is whether President Bush's top political adviser told his boss the truth about his connection to the case.
Two years ago, the White House denied that Karl Rove played any role, but revelations in the past month have shown that Rove spoke with two journalists about the operative, Valerie Plame. Whether Bush knew the truth while the White House was issuing its denials is not publicly known.
White House spokesman Scott McClellan was so adamant in his denials in September 2003 that he told reporters the president knew that Rove wasn't involved in the leak.
"How does he know that?" a reporter asked, referring to the president.
"I'm not going to get into conversations that the president has with advisers or staff," McClellan replied.
Special Counsel Patrick Fitzgerald questioned Bush a year ago and the prosecutor's office has questioned Rove repeatedly, so presumably investigators know the answer to what, if anything, Rove told Bush.
Whether Rove shaded the truth with Bush two years ago is a potential political problem. The president so far has stood by Rove's side, even raising the bar for dismissing subordinates. Two years ago, Bush pledged to fire any leakers, but now he says he would fire anyone who committed a crime.
If Rove didn't tell Bush the truth, that theoretically could be a legal problem for the presidential aide under the federal false statement statute.
Wayne State University law professor Peter Henning said the false statement law covers statements made to all members of the executive branch, including the president acting in his official capacity. In contrast, a typical false statement case involves lying to investigators or writing false information on a form to the government.
The difficulties in bringing even a typical false statement case are considerable. Simply misleading someone isn't enough to bring a prosecution.
"If the president asks Rove, `Do we have anything to worry about here?' and Rove says `No,' that would not be a false statement," said Henning. "These two men have known each other a long time, the president is not going to question Rove closely as a law enforcement agent would, and that makes all the difference."
Henning is a former federal prosecutor in the Justice Department's fraud section in Washington and has written a law school textbook on white-collar crime.
What is clear about Rove is that after the White House's public denials in 2003 saying Rove wasn't involved in the leak, the presidential aide told investigators behind closed doors about his conversations regarding Plame.
Asked whether it wants to retract its earlier denials, the White House refuses to comment on the grounds that the criminal investigation is ongoing.
Lewis Libby, Vice President Dick Cheney's chief of staff, and apparently at least one other government official were involved in leaking information to reporters about Plame, the wife of Bush administration critic and former U.S. Ambassador Joseph Wilson.
Presidential scholars say a White House's refusal to comment can suggest an administration in political trouble.
"When under fire they suddenly hide behind the shield of secrecy as though they have no control over the matter," said Mark J. Rozell, a public policy professor at George Mason University who has written five books on the presidency.
"What we really don't know factually is whether Rove lied to the president or whether the president knew something about Rove's role and dissembled," said Rozell.