The president pro tempore of the Senate is the second-highest official in the United States Senate, after the vice president, who is the president ex officio of the Senate. Typically, the person holding this position is the senior senator of the majority party, and the highest ranking member of the Senate as a result. This position is primarily ceremonial, and it comes with numerous responsibilities and rather limited powers. It is considered a great honor to serve in this role, however, not least because it puts a senator third in the line of presidential succession.
This position was first outlined in 1789 in the Constitution. When the vice president is not available to preside over the Senate, the president pro tempore has the power to preside, governing proceedings and making rulings on points of procedure. It is not uncommon for this person to allow a junior senator to preside, giving the less experienced lawmaker a chance to learn more about how the Senate works. The official is entitled to a slightly larger staff than other senators, thanks to the increased responsibility associated with the position.
The Senate officially elects a member to this job, although by convention, the position is awarded to the senior member of the majority party, and the election is typically unanimous. In the event that the party majority changes and the senator remains in office, he or she becomes the emeritus president pro tempore. This is a mark of respect when the position is assumed by the senior member of the new majority party.
It is also possible to see an acting president pro tempore, an official who is appointed to take over when the person holding the position is incapacitated or disabled. Acting presidents are not in line for the office of the president, and they will be passed over in the event of a situation where the president and vice president are incapacitated. As a gesture of courtesy, former presidents and vice presidents are considered deputy presidents pro tempore, although it is extremely unusual for these officials to serve in the Senate after their terms are over.
A number of ceremonial duties accompany this position, and the official is usually expected to preside over major Senator proceedings. Due to his or her senior rank, he or she also usually has a number of committee obligations and other responsibilities. In recognition for the additional work which accompanies the position, it is compensated more than other senators.