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
Trade union early 1979, when a significant percentage of the nation's public sector workers went on strike. By this stage, some 12,000,000 workers in the United Kingdom were trade union members. However, the election of the Conservative Party led by Margaret Thatcher at the general election in May 1979, at the expense of Labour's James Callaghan, saw substantial trade union reform which saw the level of strikes fall. The level of trade union membership also fell sharply in the 1980s, and continued falling for most of the 1990s. The long decline of most of the industries in which manual trade unions were