depends on what the meaning of "is" is,

For Republicans it's no big deal to lie to a grand Jury. It's only impeachable if it “is” a Clinton. Not a crime when Carl Rove lies to obstruct justice.

WASHINGTON - Top White House aide Karl Rove has been told by prosecutors he won't be charged with any crimes in the investigation into the leak of a CIA officer's identity, his lawyer said Tuesday, lifting a heavy burden from one of Bush's most trusted advisers.
Rove testified five times before a grand jury, most recently in April. He has admitted he spoke with columnist Robert Novak and Time magazine reporter Matt Cooper in the days before they published Plame's name in July 2003.
Rove, however, did not originally tell prosecutors about his conversation with Cooper, only revealing it after his lawyer discovered a White House e-mail that referred to it.
Fitzgerald was investigating whether Rove lied or obstructed justice in failing to initially disclose the conversation. The presidential aide blamed a faulty memory and sought to testify before the grand jury after finding the e-mail to correct his testimony.
The threat of indictment had hung over Rove, even as Rove was focusing on the arduous task of halting Bush's popularity spiral and keeping Democrats from capturing the House or Senate in November elections.
Clinton should have blamed a “faulty memory” as Rove did. The lesson here is that when you commit Treason you should blame a faulty memory, that works for Bush.