He returned to Winnipeg in 1877, and ran unsuccessfully for the constituency of Rockwood in the provincial elections of 1878 and 1879. Previously a supporter of French language rights, Clarke was by this time campaigning against bilingualism and state funding for Catholic schools. Despite this, he later defended twenty-five followers of Louis Riel in court, after the second Riel Rebellion of 1885. Clarke died near Medicine Hat in 1889, while travelling by train.