John Thomas Hackett QC (June 12, 1884 – September 15, 1956) was a lawyer and political figure in Quebec. He represented Stanstead in the House of Commons of Canada from 1930 to 1935 and from 1945 to 1949 as a Conservative and then as a Progressive Conservative member. He sat for the Victoria division in the Senate of Canada from 1955 to 1956. Hackett died in office at the age of 72.