In Section 2 of Article Two of the U.S. Constitution, the President shall be the Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States when called into actual service. The President has the power to require written opinions from the principal officers of executive departments on matters related to their duties. The President also has the power to grant reprieves and pardons for offenses against the United States, except in cases of impeachment. Furthermore, the President, with the advice and consent of the Senate, can make treaties, appoint ambassadors, public ministers, consuls, judges of the Supreme Court, and other officers of the United States. The President also has the power to fill vacancies that may happen during the Senate's recess by granting commissions that expire at the end of the Senate's next session.