The decision on Libby caught official Washington by surprise and put the Bush White House on the defensive amid criticism from opposition Democrats. Libby was convicted in March of perjury and obstruction of justice for misleading investigators probing who leaked the identity of former CIA covert officer Valerie Plame Wilson in 2003.
President Bush defended his decision to commute Libby's 30-month jail sentence in a brief exchange with reporters Tuesday.
"I thought that the jury verdict should stand. I felt the punishment was severe. So I made a decision that would commute his sentence but leave in place a serious fine and probation."
Among those condemning the president's decision was former Ambassador Joseph Wilson. Wilson is married to Valerie Plame Wilson and has long accused the Bush administration of trying to discredit both him and his wife because he criticized the administration's justifications for invading Iraq.
"For him to turn around and offer clemency to a traitor in a case in which his office and the office of the vice president are directly implicated is an outrage, and America should be outraged."
The Libby commutation also sparked outrage among Democrats. Senate Democratic leader Harry Reid called the decision disgraceful while House Speaker Nancy Pelosi said the act shows the president, in her words, condones criminal conduct. The canceling of Libby's jail sentence is also having an impact on the 2008 presidential race. Democratic frontrunner Hillary Clinton spoke out during a campaign appearance in Iowa.
"And what we saw today was elevating cronyism over the rule of law."
Conservatives were generally pleased with the president's decision on Libby, though some argue he should have gone further and given Libby a full pardon. That is still possible at some point in the future, and the president said he has ruled nothing in or out when asked about the prospect of an eventual pardon. New York Republican Congressman Peter King is among those pleased with the president's action.
"President Bush did the right thing. Scooter Libby is a good man. This was an investigation into Libby even though the prosecutor knew all along that Scooter Libby had not committed any underlying crime, he was not involved in the leaking of Valerie Plame's name. So this was an excessive sentence."
The U.S. Constitution gives presidents the right to pardon those convicted of crimes or commute their prison terms. It is a right that presidents have exercised since the earliest days of the Republic.
Professor P.S. Ruckman is an expert on the presidential pardon power at Rock Valley College in Illinois.
"George Washington did not exercise the clemency power his first term. In his second term, he ended it with a flurry of pardons and every president since then has granted at least one pardon, here and there."
Political and legal analysts say the president's decision on Libby will become part of his historical legacy and is likely to be a source of debate for sometime to come. Jonathan Turley is a professor at George Washington University Law School.
"On every level, this commutation is very curious. This is not a president who gives out commutations. It is very hard to get a commutation without serving (jail) time and this is not a particularly harsh sentence when you look at who the defendant was and what he was convicted of."
Some Democrats warn that the Libby commutation will make them less likely to cooperate with the president in the final months of his term. But some political analysts say the Libby decision could help repair relations between Mr. Bush and conservative Republicans.
Those ties have become strained in recent months because of the president's handling of the Iraq war and his support of an immigration reform bill opposed by many conservatives that was recently defeated in Congress.