In 1904, he was appointed to the Laurier Cabinet as Minister of Inland Revenue where he introduced anti-trust legislation to protect tobacco farmers from the monopolistic practices of the American Tobacco Company.
In 1906, he was promoted to Minister of Marine and Fisheries and reorganized the Montreal Harbours Commission and instituted reforms in the department to reduce patronage and corruption.
In 1910, he became Minister of the Naval Service and was responsible for introducing legislation to create the Canadian Navy. This signified a move towards Canadian independence from Britain. It was opposed by the Conservative Party, which preferred Canada's participation in the British Navy. By the end of his term, the new Navy consisted of 233 sailors and two cruisers, one on each coast. The policy of creating a Canadian Navy was also opposed by French-Canadian nationalists such as Henri Bourassa who feared that the Canadian Navy would only be used as a device to engage Canada in British wars.
1The office of Minister of Marine and Fisheries was abolished and the offices of Minister of Fisheries and Minister of Marine were created in 1930 2The offices of Minister of Marine and Minister of Railways and Canals were abolished and the office of Minister of Transport was created in 1936 3From 1971 to 1976 the Minister of the Environment was also the Minister of Fisheries.