Máiría Cahill is elected to Seanad Éireann on November 13, 2015 after winning a by-election held to fill the seat left vacant after the resignation of the Labour Party‘s Jimmy Harte. She wins 122 of the 188 valid votes cast in an election in which only Teachta Dálas (TDs) and Senators can cast a vote.
Cahill is born in 1981 into a prominent republican extended family in West Belfast. Her great-uncle Joe Cahill is one of the founders and chief of staff of the Provisional Irish Republican Army (IRA) in the 1970s. She is a cousin of both Siobhán O’Hanlon, a prominent republican activist in the IRA and later in Sinn Féin until her death in 2006, and her sister Eilis O’Hanlon, a political commentator for the Irish Independent and critic of both the IRA and Sinn Féin. She also claims her grandfather recruited Gerry Adams into the IRA.
Cahill is elected National Secretary of Ógra Shinn Féin and works for Sinn Féin between 1998 and 2001. She quits Sinn Féin in 2001 when she moves to the United States. She later returns and works on two election campaigns for the party before growing disillusioned at her treatment and leaving for good.
In February 2015, Cahill receives a James Larkin Thirst for Justice award from the Irish Labour Party. In November 2015, she receives a Special Recognition Award in the Irish Tatler‘s Woman of the Year Awards.
In October 2015, Labour Party leader Joan Burton announces Cahill has joined the party and she, along with her deputy Alan Kelly, will put her forward as the party’s nominee in a by-election to Seanad Éireann’s Industrial and Commercial Panel. The by-election has been occasioned by the resignation of Senator Jimmy Harte due to illness. Cahill secures the party’s nomination unopposed and wins the election in November 13 on the first count, with 122 first preferences out of 188 valid votes from Oireachtas members.
Cahill is criticised by Senator David Norris for failing to satisfactorily answer questions on her links to dissident republican groups and for failing to take part in media debates with other candidates. Norris later states that she is “an interesting and vital voice in Seanad Éireann.”
In a March 2016 interview with Catherine Shanahan of the Irish Examiner, Kathleen Lynch, a former Labour party TD and Minister of state, states she has no idea as to why Cahill was chosen as the party’s by-election candidate. Cahill does not contest the 2016 Seanad elections.
Cahill is co-opted into a Social Democratic and Labour Party (SDLP) council seat in Lisburn and Castlereagh council in July 2018. She has to withdraw from the local election campaign in April 2019, due to a law requiring candidates to publish their home addresses. Cahill is unable to do so due to threats made against her. The British Government subsequently apologises.