Former White House aide I. Lewis "Scooter" Libby has been sentenced to 30 months in prison and a fine of $250,000 for perjury and obstruction of justice in the CIA leak case. He also will serve two years probation following the prison term.

Libby stood calmly as a federal judge said the evidence had overwhelmingly proven his guilt. The judge said people in positions like the one Libby held -- chief of staff to Vice President Dick Cheney -- "have a special obligation to not do anything that might create a problem."

Libby was convicted in March of lying and obstructing an investigation into the 2003 leak of CIA operative Valerie Plame's identity.