Working against the clock, special prosecutor Patrick Fitzgerald weighed criminal charges against two top presidential aides at the end of a two-year investigation that put President George W. Bush's White House in a state of high suspense. Fitzgerald faced a Friday expiration of the grand jury that has been investigating the exposure of covert CIA officer Valerie Plame's identity. That, if done intentionally, can be a federal crime. Speculation flew across Washington about who would be indicted, or whether Fitzgerald would even bring criminal charges. At the top of the list: Bush's top political adviser, deputy chief of staff Karl Rove and vice presidential chief of staff I. Lewis "Scooter" Libby. Both men put in their normal long day Thursday at the White House. The prospect of indictments added to the woes of an administration already facing serious political problems. Both Rove and Libby have been advised that they could be charged with wrongdoing, possibly for false statements to the grand jury that has been hearing testimony about discussions with reporters about Plame's identity. Other possible charges are obstruction of justice or perjury, along with possible violations of a law barring disclosure of the identity of a covert intelligence agent.