Grimes joined the
Australian Labor Party in 1968, after previously joining the
British Labour Party during his time in England. He was given the social security portfolio. In March 1980, Grimes was suspended from parliament for 24 hours for using the words "pimp" and "fascist" and accusing Prime Minister
Malcolm Fraser of "setting up" a demonstration outside a nursing home at which nine people were arrested. After the ALP won the
1983 election, Grimes was appointed
Minister for Social Security in the
Hawke government. He was also elected Deputy Leader of the Government in the Senate. In a cabinet reshuffle in 1984 he was given the new position of
Minister for Community Services. In October 1986, Grimes announced that he would not seek re-election. He resigned from Parliament in April 1987, but the
casual vacancy was not immediately filled because the Tasmanian Parliament stalemated over the appointment of the Labor Party's nominee as replacement senator,
John Devereux. ==Later life==