When convicted of a federal crime, you can ask to be pardoned for your crimes, but only from the President of United States of America. The pardon application goes through the Department of Justice through the office of the Pardon Attorney.
The President has the power to grant amnesty, commute a sentence, or grant a full pardon for any offense against the United States. However, the President cannot pardon a person for an offense committed against a state. Amnesty means that you are immune from prosecution for a specific act. The best example, would be granting amnesty to all people who peacefully resisted being drafted for a war they opposed. In that instance, if the government was about to charge draft dodgers with a crime, the president could grant amnesty to all of those people.
A commutation is where the President does not remove the record of the conviction, but removes all of part of a sentence. An example of this is when I. Lewis “Scooter” Libby was convicted of crimes, he received a sentence of 30 months in jail. Then President George W. Bush commuted the sentence. In that instance, Libby still remains a convicted felon.
A pardon full removes the conviction, and reinstates all rights of the individual to their rights as they were before the prosecution that caused them to be convicted.
Clemency is a word used to describe the entire umbrella of pardons, commutations and amnesty.
