In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
Q: In the United States, the pardon power for federal crimes is granted to the President of the United States under Article II, Section 2 of the United States Constitution which states that the President 'shall have power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment'. The U.S. Supreme Court has interpreted this language to include the power to grant pardons, conditional pardons, commutations of sentence, conditional commutations of sentence, remissions of fines and forfeitures, respites, and amnesties.
A: 
why does the president have power to pardon