What Powers Presidents Have to Set Prisoners Free

— -- "The president ... shall have power to grant reprieves and pardons for offenses against the United States."

It’s one phrase -- just 16 of the 4,543 words that make up the U.S. Constitution. But for tens of thousands of Americans who have found themselves incarcerated in federal prisons over the years, those words have meant freedom.

President Obama has used the power to grant 64 pardons and commute the sentences of 89 other Americans in his first seven years in the White House, according to the Justice Department. Those cases are a tiny fraction of the 20,000 petitions for a reprieve Obama has received -- more than any other president in history. Before he leaves office, he's expected to grant many more.

Commutations By President

Since Jimmy Carter’s presidency in 1977 the White House has received 35,201 petitions for commutations. Only 206, or 0.6 percent have been granted.

“The power to grant pardons and clemency is one of the most profound authorities granted to a President of the United States," Obama says in his letter to inmates that have their sentences commuted by him. It is not a matter that presidents take lightly.

Power to Commute and Pardon

There are two forms of executive clemency. A “commutation” is what may be granted to someone who is currently incarcerated. The president may reduce a sentence, either totally or partially, and may also include remission of any unpaid fines or restitution imposed as part of the sentence.

A “pardon” is the forgiveness of a crime. It is only available after the person has served a sentence and exhibits good conduct in free society for at least five years. Normally, a pardon is in recognition of the applicant’s acceptance of responsibility for the crime, and does not suggest innocence. Those who receive a pardon are generally returned the rights to vote, hold some political offices, and even sit on a jury.

Birth of the Presidential Pardon

The concept of executive clemency emerged in common law hundreds of years ago, and was codified by the British empire, with the king possessing nearly universal power to pardon as he saw fit. It wasn’t without controversy, as churches, feudal courts, and Parliament felt they should also wield the power. In its early years, the power to pardon was often abused for political gain, bribery, and even “arbitrary and irrelevant” reasons, as Parliament once complained.

By the time executive clemency was written into the U.S. Constitution, much of the ethics surrounding the authority had been hammered out. Still, when the nation’s first president issued his first pardon, he managed to generate a great deal of controversy. In July 1795, George Washington sought to quell the Whiskey Rebellion by pardoning two of its participants, who had been sentenced to hang for treason. Washington’s clemency was seen by many as a return to exactly the kind of authoritarian power from which the new nation had just broken away.

Nixon: A Pardoner and Pardoned

Richard Nixon is the only American to find himself on both ends of presidential clemency. As president in 1971, Nixon commuted the sentence of Teamster Union President James Hoffa. Interestingly, Hoffa contested a provision of the commutation requiring him to refrain from contact with the union. However, Hoffa disappeared before the matter was resolved, and he has never been found.