Twenty-second Amendment to the United States Constitution
The amendment prohibits any individual who has been elected president twice from being elected again. Under the amendment, an individual who fills an unexpired presidential term lasting greater than two years is also prohibited from winning election as president more than once. Scholars debate whether the amendment prohibits affected individuals from succeeding to the presidency under any circumstances or whether it only applies to presidential elections.
Thirteenth Amendment to the United States Constitution
While the Constitution does not provide the President any formal role in the amendment process, the joint resolution was sent to Lincoln for his signature. Under the usual signatures of the Speaker of the House and the President of the Senate, President Lincoln wrote the word "Approved" and added his signature to the joint resolution on February 1, 1865. On February 7, Congress passed a resolution affirming that the Presidential signature was unnecessary. The Thirteenth Amendment is the only ratified amendment signed by a President, although James Buchanan had signed the Corwin Amendment that the 36th Congress had adopted and sent to the states in March 1861.