Jimmy Hoffa Agreement. He played a major role in the growth and development of the union, which eventually became the largest (by membership) in the United States with over 2.3 million members at its peak, during his terms as its leader. Hoffa became involved with organized crime from the early years of his Teamsters work, and this connection continued until his disappearance in 1975. He was convicted of jury tampering, attempted bribery and fraud in 1964, in two separate trials. He was imprisoned in 1967 and sentenced to 13 years. In mid-1971, he resigned as president of the union as part of
Jimmy Hoffa or imprisoned for virtually all of the 1960s. Hoffa was re-elected, without opposition, to a third five-year term as president of the IBT, despite having been convicted of jury tampering and mail fraud in court verdicts that were stayed pending review on appeal. Delegates in Miami Beach also elected Frank Fitzsimmons as first vice-president, to become president "if Hoffa has to serve a jail term". Hoffa had first faced major criminal investigations in 1957, as a result of the McClellan Senate hearings. He avoided conviction for several years. However, when John F. Kennedy was elected president in 1960, he appointed