 Des Vœux then moved to Canada, where he finished his BA at the University of Toronto and became a barrister in Upper Canada in 1861.Des Vœux became stipendiary magistrate and superintendent of rivers and creeks in British Guiana from 1863 to 1869, where he championed native causes.He reorganised and codified old French system of law when he was the Administrator and Colonial Secretary of St. Lucia between 1869 and 1880.