There was no word on when Libby would begin serving his sentence. He was also fined $250,000 and is to be on probation for two years after he gets out of prison.
Libby was convicted of four counts of lying to investigators and obstruction of justice, stemming from the leak of the name of CIA operative Valerie Plame, the wife of former Ambassador Joseph Wilson, who clashed with the administration over whether Saddam Hussein tried to buy yellow cake uranium from Niger. Libby wasn't charged, however, with the actual leak and has maintained his innocence.
He has previously said he planned to appeal the conviction and Tuesday asked the court to consider his whole life in deciding on the sentence.
"I realize fully the court must decide on punishment along with the jury," Libby said. He then asked the court to consider his "whole record."
Court TV reported there was no letter from Libby's boss, U.S. Vice President Dick Cheney, his former boss, among submissions to the court on Libby's behalf.
Special Prosecutor Patrick Fitzgerald asked the court to sentence Libby to 30- to-37 months in prison. The defense sought probation. Walton said he had to consider the key fact that Plame's name was released although no one was charged with the actual leak.
Libby, Cheney's former chief of staff and the highest White House official to be convicted since the Iran-Contra scandal, was convicted three months ago.
Walton rejected a recommendation by the federal probation office that Libby be incarcerated for 15 to 21 months.
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