French Revolutionary leader who in 1791 introduced in the National Assembly the Loi (“Law”) Le Chapelier, which made any association of workers or of employers illegal. In force until 1884, the law actually affected only workers, who found it much more difficult to conceal their activities than employers did.

Beginning his career as a barrister, Le Chapelier in 1789 was elected to the Estates-General as a deputy of the Third Estate (the bourgeoisie, or middle class) for Rennes. He founded the Club Breton at Versailles, which was the precursor of the Jacobin Club, and was president of the National Assembly (August 1789). But after Louis XVI's flight to Varennes in 1791, Le Chapelier allied himself with the moderate reformers. He left the Jacobins and joined the Feuillants, a group that advocated limiting the vote to property owners. Le Chapelier was arrested and executed (1794) during the Reign of Terror after his return from a visit to England.