 In 1855, he became a member of the municipal council for Montreal.In 1856, he was elected to the Legislative Council of the Province of Canada for Thousand Islands division; he was defeated by Léandre Dumouchel in 1864 when he ran again in the same division.Masson founded a settlement at Sainte-Marguerite, which later became the parish of Sainte-Marguerite-du-Lac-Masson.