Twenty-second Amendment to the United States Constitution
Some argue that the 22nd Amendment and 12th Amendment bar any two-term president from later serving as vice president as well as from succeeding to the presidency from any point in the presidential line of succession. Others contend that the original intent of the 12th Amendment concerns qualification for "service" (age, residence, and citizenship), while the 22nd Amendment, concerns qualifications for "election", and thus (strictly applying the text) a former two-term president is still eligible to "serve" as vice president (neither amendment restricts the number of times an individual can be elected to the vice presidency), and then succeed to the presidency to serve out the balance of the term (though prohibited from running for election to an additional term).
President of the United States
Pursuant to the Twentieth Amendment, the four-year term of office for both the president and vice president begins at noon on January 20. The first presidential and vice presidential terms to begin on this date, known as Inauguration Day, were the second terms of President Franklin D. Roosevelt and Vice President John Nance Garner in 1937. Previously, Inauguration Day was on March 4. As a result of the date change, the first term (1933–37) of both men had been shortened by days.