A Paris advocate elected for the Third Estate of the city, Treilhard took the Tennis Court Oath and, on the ecclesiastical committee, carried the decrees on the sale of Church property and the Civil Constitution of the Clergy. Elected to the Convention for Seine-et-Oise, he presided over part of Louis XVI’s trial and voted for death with a reprieve. He sat on the Committee of Public Safety in 1793 and twice again after Thermidor, and was recalled from mission at Bordeaux for moderantism. Elected a Director in May 1798, he was removed in June 1799 when the councils annulled his election as unconstitutional, his year of ineligibility not having expired. As a councillor of state under the Consulate and Empire he took a substantial part in framing the codes. He died in Paris in 1810.