The Vice President’s Tie-Breaking Votes
Article I, section 3, clause 4 of the Constitution designates the vice president as the Senate’s presiding officer. And Article I, section 5, clause 3 stipulates that any senator may call for a recored vote with a sufficient second (anywhere from 11 to 20 members depending on how many senators are present). When the Senate divides evenly on recorded votes, the Constitution empowers the vice president to cast the tie-breaking vote.
The Senate’s precedents include two examples of what happens when the vice president casts a tie-breaking vote in his or her capacity as the institution’s presiding officer. The vice president may say,
“Senators, on this question the yeas are ___ and the nays are ___. The Senate being equally divided, the Vice President votes in the ___ and the (proposition) is ___.”
The vice president may also say,
“The Senate being equally divided, the Vice President declares the (proposition) lost or disagreed to.”
The Constitution does not require the vice president to vote when the Senate is tied.
The Senate Historical Office maintains a list depicting the number of times vice presidents have cast tie-breaking votes in the Senate. According to the document, vice presidents have cast 268 tie-breaking votes in their capacity as the Senate’s presiding officer between 1789 and 2018.
The first tie-breaking vote cast by the vice president happened on July 18, 1789. (John Adams was the vice president at the time.) Vice President Mike Pence cast the last tie-breaking vote on December 21, 2018.