In 1792, Congress put the president pro tempore of the Senate and the speaker of the House, in that order, in the line, behind the vice president. It added no others.

In the aftermath of the Kennedy assassination, however, the current order of Presidential succession has come under critical examination.

When the U.S. Constitution was written in the late 18th century, it provided a sparingly short order of succession, making the vice president first in a line of one to take over for the president.

We don’t know how. But if the order bypasses the speaker and the Senate president pro tempore in favor of an official in the executive branch, we have a recipe for a constitutional crisis.

The U.S. Constitution and the Presidential Succession Act of 1947 outline the presidential order of succession. The line of succession of cabinet officers is in the order of their agencies ...

If a president has not been chosen by inauguration day, the Presidential Succession Act provides “… the Speaker … shall, upon … resignation as Speaker, and as Representative in Congress ...