Career
Born in Neche, North Dakota, Dumas came to Manitoba in 1897. He worked as a construction contractor. Dumas was elected to the Manitoba legislature in the 1915 provincial election, defeating a Conservative and an independent Liberal candidate in the constituency of Saint Boniface.
He ran for re-election in the 1920 campaign, but finished third against Conservative-Independent candidate Joseph Bernier.
In 1935, Dumas moved to California. He died in Saugus, California.