Career
He was elected as a Sinn Féin Member of Parliament for the Wexford North constituency at the 1918 general election. In January 1919, Sinn Féin MPs refused to recognise the Parliament of the United Kingdom and instead assembled at the Mansion House in Dublin as a revolutionary parliament called Dáil Éireann. In the Dáil debate of 25 January 1921 on "Truce negotiations", Sweetman was alone in disapproving of the conduct of the Irish War of Independence, and particularly the events of Bloody Sunday.
He did not contest the 1921 elections.