 From 1888 to 1992 and again from 1913, to fill the seat vacated by A. H. Garland, who left the state, until 1932, Dupré was a Democratic member of the Louisiana House of Representatives.He served as a state district court judge by election from 1896 to 1900 and by appointment in 1914.He was elected judge in 1916, 1920, and 1924, while he also served in the part-time legislative post.