François Xavier Martin (March 17, 1762 – December 10, 1846), was a Franco-American lawyer and author, the first Attorney General of State of Louisiana, and longtime Justice of the Louisiana Supreme Court. Born in Marseille, he moved to Martinique in 1780, and then immigrated to North Carolina just before the end American Revolutionary War. He was appointed as Attorney General of the Territory of Orleans after the Louisiana Purchase; he also helped untangle layers of French and Spanish colonial law in the territory and subsequent state of Louisiana. His legal writing and reviews of cases was important to codification of Louisiana law in the 1820s.
Likely his most well-known case in his decade as Chief Justice of the Louisiana Supreme Court was that of the freedom suit of Sally Miller, in Miller v. Belmonti (1845 La). The court ruled to free Miller, a slave of obvious European descent, in part based on her appearance; the presumption was that she was "white" (European American), and the defendants had not sufficiently proved that she was enslaved. The decision was unpopular in the South and contributed to the Louisiana Constitutional Convention's abolishing the state Supreme Court in March 1846, ending Martin's career at the age of 84. The following day, the convention reinstated the court but did not reappoint Martin or his five colleagues.