Career
She was previously a Progressive Democrats Teachta Dála (Territorial Decoration) for the Longford–Roscommon constituency from 2002 to 2007. She is a native of the townland of Glack, near Longford town. She stood at the 1992 general election in Longford–Roscommon as an independent candidate, but obtained only 1,160 first preference votes (26%), and was eliminated, failing to be elected.
She was re-elected to both Longford Urban District and County Councils in the 1999 local elections, although her first preference vote for both bodies had declined.
She stood again at the 2002 general election. Her election in 2002, in a predominantly rural midland constituency for a party often associated with the urban middle classes was one of the major surprises of that election, and came after a series of near misses from elimination during the progress of the election count.
In Dáil Éireann
Sexton maintained an active profile within County Longford during her time as a Dáil deputy and built a minor profile nationally as a panellist on political discussion programmes on radio and television In June 2005, she attracted attention by calling for the Irish government to abandon plans for a referendum on the European Constitution after the defeats of the referendums in France and the Netherlands.
2007 general election
County Longford was included in a new Longford–Westmeath constituency.
At the 2007 general election she lost her seat, polling only 2,298 first preference votes (42%) in the new constituency and being eliminated on the third count. Unofficial tally figures published in local newspapers showed that her vote had halved in her County Longford base, while she received negligible support in County Westmeath. After the poor performance of the PDs in the election, she said in an interview with local radio that she was still committed to the party.
2009 local elections
With the dissolution of the Progressive Democrats in 2009, Sexton stood as an independent candidate at the 2009 local elections in Longford.
She regained her seats on both the Longford County and Town Councils. Labour Party (2010-2012)
In April 2010, the Labour Party announced that Sexton had accepted an invitation to join the party.
Sexton ran in the 2011 general election in Longford–Westmeath alongside sitting Labour Territorial Decoration Willie Penrose. She was unsuccessful garnering 3,960 votes or 6.8% of the poll.
She left the Labour Party in December 2012, citing concerns over the budget.