In November 1920, breaking ranks with Sinn Féin, Sweetman wrote to the press calling for a truce and peace negotiations in the Irish War of Independence, and criticising Irish Republican Army actions, in particular the assassinations on Bloody Sunday. He was criticised for this when the Dáil next met on 25 January 1921. Two days later he announced his resignation as Teachta Dála (TD, Dáil deputy) because of his "radical disagreement with the majority ... on a vital matter of policy". He did not contest the June 1921 election. Thereafter he concentrated on farming, promoting use of Friesian cattle in dairy farming.