Oath of office of the President of the United States

The oath of office of the President of the United States is the oath or affirmation that the President of the United States takes after assuming the presidency but before he or she begins the execution of the office. The wording of the oath is specified in Article II, Section One, Clause 8 of the United States Constitution.

This clause is one of two oath or affirmation clauses, but it alone actually specifies the words that must be spoken. The other, Article VI, Clause 3 simply requires the persons specified therein to "be bound by oath or affirmation, to support this Constitution." The presidential oath on the other hand, requires much more than this general oath of allegiance and fidelity. This clause enjoins the new president to swear or affirm that he "will to the best of his ability, preserve, protect and defend the Constitution of the United States."

Before he enter on the Execution of his Office, he shall take the following Oath or Affirmation:—"I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my ability, preserve, protect and defend the Constitution of the United States."

While the Constitution does not mandate that anyone in particular should administer the presidential oath of office, it is typically administered by the Chief Justice. There have been several exceptions, however. George Washington was sworn into office during his first inauguration, on April 30, 1789, by Chancellor of New York Robert Livingston.William Cranch, chief judge of the U.S. Circuit Court, administered the oath to Millard Fillmore on July 10, 1850, when he became president after the death of Zachary Taylor. Upon being informed of Warren Harding's death, while visiting his family home in Plymouth Notch, Vermont, Calvin Coolidge was sworn in as president by his father, John Calvin Coolidge, Sr., a notary public.Federal Judge Sarah T. Hughes administered the oath of office to Lyndon B. Johnson aboard Air Force One after John F. Kennedy's assassination on November 22, 1963. Overall, the presidential oath has been administered by 15 Chief Justices, one Associate Justice, three federal judges, two New York state judges, and one notary public.

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