Prosecutor Patrick Fitzgerald told the court Libby's lies created a "house of mirrors" for investigators, reports CBS News correspondent Bob Orr. Fitzgerald implored the judge to impose a tough sentence "to make it clear the truth matters."
Defense lawyer Ted Wells cited what he called Libby's "exceptional public service to our nation" that, he argued, "justifies a sentence of probation."
But U.S. District Judge Reggie B. Walton, known as "long ball" for his harsh judgments, was unmoved, sentencing Libby to 30 months in prison and a $250,000 fine, adds Orr.
"People who occupy these types of positions, where they have the welfare and security of nation in their hands, have a special obligation to not do anything that might create a problem," Walton said.
Walton did not set a prison date for Libby, the former chief of staff to Vice President Dick Cheney. Though he saw no reason to let Libby remain free pending appeal, Walton said he would accept written arguments on the issue and rule later.
Cheney, who said he was "saddened" by the verdict, described Libby in a statement as a man "of the highest intellect, judgment and personal integrity — a man fully committed to protecting the vital security interests of the United States and its citizens."
President Bush, in Europe for the G-8 Summit, said he felt "terrible" for Libby's family, but does not intend to intervene now in his case.
The U.S. Bureau of Prisons will decide where Libby serves his sentence and set a reporting date. The agency tries to place prisoners close to home whenever possible.
Libby was convicted in March of lying and obstructing an investigation into the 2003 leak of CIA operative Valerie Plame's identity.
The highest-ranking White House official convicted in a government scandal since the Iran-Contra affair, Libby has steadfastly maintained his innocence.
"It is respectfully my hope that the court will consider, along with the jury verdict, my whole life," Libby said in brief remarks to the judge. He also thanked the judge and the court's personnel for the "consideration and courtesies" over the past year and a half. Libby told the judge that he realized "fully that the court must decide on punishment," reports CBSNews.com's Jennifer Hoar, after which Judge Walton paused introspectively.
Sitting with Libby's wife, Harriet Grant, during the sentencing were conservative commentators Mary Matalin, a former Cheney aide, and Victoria Toensing, a former deputy assistant attorney general during the Reagan administration. During a 10-minute recess after the sentence was read, Grant was tearful as she hugged several people around the defense table, Hoar reports.
"The sentence and fine were at the high end of the range of options here for Judge Walton, but it's really no surprise given the judge's reputation for tough sentences and his view of Libby's conduct," CBS News legal analyst Andrew Cohen said.
"Libby's lawyers have said that they will appeal his conviction, and now his 2 1/2-year-long sentence, and that probably won't be resolved by a federal appeals court until well into next year. To me, that increases the chances of a presidential pardon, especially if Libby, as expected, loses his appeal," Cohen said.
With letters of support from several former military commanders and White House and State Department officials, Libby asked for no jail time. His supporters cited a government career in which Libby helped win the Cold War and the first Gulf War.
"He has fallen from public grace," defense attorney Theodore Wells said. "It is a tragic fall, a tragic fall." Unlike in his bombastic closing arguments during the Libby trial, Wells spoke gently, almost cautiously, as he asked that his client be spared incarceration, Hoar says.