The 25th Amendment has been in the news a lot recently. As this year marks the 50th anniversary of its ratification, let’s explore each section of this oft-discussed amendment and what led us there.

SECTION 1: “IN CASE OF THE REMOVAL OF THE PRESIDENT FROM OFFICE OR OF HIS DEATH OR RESIGNATION, THE VICE PRESIDENT SHALL BECOME PRESIDENT”

First, a question: How many presidents have there been? Some say 45, others will remember Grover Cleveland’s nonconsecutive terms and say 44. Less well known is that there was a very serious question following William Henry Harrison’s death in 1841: Was John Tyler now president?

The Constitution specifies that the duties of the presidency shall “devolve on the Vice President” but does not specify that the actual title (or, among other things, the salary increase) goes to the VP. As the Senate was debating the issue after Harrison’s death, Senator Benjamin Tappan of Ohio made the analogy that “If a colonel was shot in battle, the next officer in rank took command of the regiment, but he did not thereby become a colonel.”

Another senator, referring to Tyler, attempted to strike out the word “president” in a procedural document and replace it with “the Vice President, on whom, by the death of the late President, the powers and duties of the office of President have devolved.” The measure was struck down 38-8. Tyler would ultimately fully assert that he was the president in duties as well as title, which created a precedent that lasted for more than 120 years. But it was just precedent, and some later presidents in similar situations—especially Millard Fillmore—were still labeled “Acting President” until the 25th Amendment finally specified, “In case of the removal of the President from office or of his death or resignation, the Vice President shall become President.”

SECTION 2: “WHENEVER THERE IS A VACANCY IN THE OFFICE OF THE VICE PRESIDENT, THE PRESIDENT SHALL NOMINATE A VICE PRESIDENT WHO SHALL TAKE OFFICE UPON CONFIRMATION”

America has gone through a few different succession crises, but it was the assassination of John F. Kennedy amidst the backdrop of the Cold War that demonstrated the need for a permanent vice president.

After Kennedy’s assassination, there were concerns about each member of the line of succession. New president Lyndon Johnson had had a heart attack in 1955; if something were to happen to him, the speaker of the house was in his 70s and the president pro tempore was in his 80s. Alongside lingering concerns about Dwight Eisenhower’s health issues, congress decided that the line of succession needed to be more robust than it was.

As Indiana Senator Birch Bayh, one of the key forces behind the amendment, said, “The accelerated pace of international affairs, plus the overwhelming problems of modern military security, make it almost imperative that we change our system to provide for not only a President but a Vice President at all times … [the Vice President] must, in fact, be something of an ‘assistant President’” who can keep track of the national and international scene and understand what’s going on with the executive branch.

So as part of the 25th Amendment, the president was given the power to fill a vacant office of the vice president, subject to votes in both houses of congress.

SECTIONS 3 AND 4: “WHENEVER THE PRESIDENT TRANSMITS … HIS WRITTEN DECLARATION THAT HE IS UNABLE TO DISCHARGE THE POWERS AND DUTIES OF OFFICE … SUCH POWERS AND DUTIES SHALL BE DISCHARGED BY THE VICE PRESIDENT AS ACTING PRESIDENT” AND “WHENEVER THE VICE PRESIDENT AND A MAJORITY OF EITHER THE PRINCIPAL OFFICERS OF THE EXECUTIVE DEPARTMENTS TRANSMIT … THAT THE PRESIDENT IS UNABLE TO DISCHARGE THE POWERS AND DUTIES OF HIS OFFICE, THE VICE PRESIDENT SHALL IMMEDIATELY ASSUME THE POWERS AND DUTIES OF THE OFFICE AS ACTING PRESIDENT"

Dwight D. Eisenhower suffered multiple health scares during his presidency. During one of them, he realized that the circumstances for replacing a president with the vice president permanently was clear, but what if the president was only temporarily incapacitated?

The first time America was faced with this issue was James Garfield. For the 80 days that he was president but unable to serve as such, there was confusion about what Vice President Chester Arthur should do. If Arthur became acting president, would the Tyler Precedent mean that if Garfield recovered he’d be unable to reclaim the presidency? Arthur was concerned this was the case, and he would be viewed as having effectively staged a coup (not helped by Garfield's assassin having said “Arthur is President now”). Anyway, who would make the decision that Garfield was incapacitated and—more importantly—fully recovered?

Arthur chose not to assume presidential responsibilities [PDF] and Garfield did die, so severe Constitutional questions were avoided, but later leaders would recognize that hope was not a valid plan.

After his 1955 heart attack, Eisenhower instructed Attorney General Herbert Brownell Jr. to explore a Constitutional amendment that would allow the vice president to be acting president until the president was able to say that he could resume the task. In the case of a president deciding that they were able to reclaim the presidency despite not really being able to, Brownell initially proposed impeachment. Eventually, the 25th Amendment specified that if the vice president and cabinet disagreed with the president, the issue would go to congress.

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