Career
He replaced John A. Lee in the electorate when Lee was expelled from the Labour Party. Cabinet Minister
He was a cabinet minister in the Fraser Ministry of the First Labour Government: Postmaster-General and Minister of Telegraphs (1946–1949), Minister of Transport (1947–1949), Minister of Marine (1947–1949), Minister in charge of the Public Trust Office (1946–1947), State Fire Insurance (1946–1947), and Government Life Insurance Department (1946–1947). In the Second Labour Government, he was Minister of Labour, Minister of Mines, and Minister of Immigration (all 1957–1960).
Hackett was opposed to New Zealand joining the International Monetary Fund, arguing that the state should have sole right to govern the country"s finances.
Walter Nash favoured Clarence Skinner and then Hackett to replace him when he retired after the 1960 election, see New Zealand general election, 1963, but with the deaths of first Skinner and then Hackett, Nash was replaced by Arnold Nordmeyer.