The Presidential Succession Act of 1947 identifies the Speaker of the House and the Senate President pro tempore as the second and third successors to the presidential seat, according to the U.S. Senate. A successor temporarily accepts presidential duties when the current president and vice president are deceased, discharged from office or unable to assume responsibility for other reasons, CNN states.
Congress eliminated the House Speaker and President pro tempore from succession in 1886, placing Cabinet members, such as the Secretary of State, further up the line, according to the U.S. Senate. Some Congress members questioned the election process for the President pro tempore and believed Cabinet positions offered a clearer demonstration of executive abilities.
Before 1886, the President pro tempore was directly behind the Vice President in line, but the 1947 act named the House Speaker as the second successor. Official accounts say President Harry Truman proposed this new legislation due to the House Speaker's position as an elected district representative with the people's vote, but the U.S. Senate also suggests that Truman had an uneasy relationship with the current President pro tempore in 1945.
In 2004, Congressman Brad Sherman proposed new reforms to presidential succession laws, which included removing the House Speaker and President pro tempore from the line, CNN reports.