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
GCHQ trade union ban GCHQ trade union ban The GCHQ trade union ban was a ban on trade union membership of employees at the Government Communications Headquarters in Cheltenham between 1984 and 1997. This was based on the claim by the Conservative government that it undermined national security. It sparked a dispute which became a cause célèbre, one of the most important trade union issues of the 1980s and the second longest continuously fought dispute in British trade union history. In 1981, a series of strikes in Whitehall over pay led to industrial action at Government Communications Headquarters (GCHQ) intelligence 'listening centre' network based