who is the constitutional presiding officer of the senate
Presiding Officer of the United States Senate The Vice President is assigned the responsibility by the Constitution of presiding over the Senate and designated as its president. The vice president has the authority (ex officio, for they are not an elected member of the Senate) to cast a tie-breaking vote. Early vice presidents took an active role in regularly presiding over proceedings of the body, with the president pro tempore only being called on during the vice president's absence. During the 20th century, the role of the vice president evolved into more of an executive branch position. Now, the vice president is usually seen as an integral part of a president's administration and presides over the Senate only on ceremonial occasions or when a tie-breaking vote may be needed.[1]