Vice President of the United States

The Vice President of the United States (informally referred to as VPOTUS, or Veep) is a constitutional officer in the legislative branch of the federal government of the United States as the President of the Senate under Article I, Section 3, Clause 4, of the United States Constitution, as well as the second highest executive branch officer, after the President of the United States. The vice president is also an officer in the legislative branch, as President of the Senate. In this capacity, the vice president presides over Senate deliberations (or delegates this task to a member of the Senate), but may only vote to break a tie. The vice president also presides over joint sessions of Congress. In accordance with the 25th Amendment, he is the highest-ranking official in the presidential line of succession and is a statutory member of the National Security Council under the National Security Act of 1947. The vice president is indirectly elected together with the president to a four-year term of office by the people of the United States through the Electoral College. Section 2 of the Twenty-fifth Amendment, ratified in 1967, created a mechanism for intra-term vice presidential succession, establishing that vice presidential vacancies will be filled by the president and confirmed by both houses of Congress. Previously, whenever a vice president had succeeded to the presidency or had died or resigned from office, the vice presidency remained vacant until the next presidential and vice presidential terms began.

The Constitution does not expressly assign the vice presidency to any one branch, causing a dispute among scholars about which branch of government the office belongs to: 1) the executive branch; 2) the legislative branch; 3) both; or 4) neither. The modern view of the vice president as an officer of the executive branch (isolated almost totally from the legislative branch) is due in large part to the assignment of executive authority to the vice president by either the president or Congress.

Vacancies
Prior to ratification of the Twenty-fifth Amendment in 1967, no constitutional provision existed for filling an intra-term vacancy in the vice presidency. As a result, when one occurred, the office was left vacant until filled through the next ensuing election and inauguration. Between 1812 and 1967, the vice presidency was vacant on sixteen occasions—as a result of seven deaths, one resignation, and eight cases in which the vice president succeeded to the presidency.

Section 2 of the Twenty-fifth Amendment established a procedure for filling such a vacancy: "Whenever there is a vacancy in the office of the Vice President, the President shall nominate a Vice President who shall take office upon confirmation by a majority vote of both Houses of Congress."

This procedure has been implemented three times since the amendment came into force. The first instance occurred in 1973 following the October 10 resignation of Spiro Agnew, when Gerald Ford was nominated by President Richard Nixon and confirmed by Congress. The second occurred 10 months later following Ford's August 9, 1974 accession to the presidency upon Nixon's resignation, when Nelson Rockefeller was nominated by President Ford and confirmed by Congress.

List of Vacancies
From the formation of the office of Vice President in 1789 to the inauguration of Greg Degurechaff as the 51st Vice President, there have been 22 vacancies in total.