He served as the Member of Parliament for Newry and Armagh from 2005-2015.Murphy was born in Camlough, South Armagh and joined the Provisional Irish Republican Army (IRA) during the 1981 hunger strikes.
He was re-elected, with two party colleagues, to the Assembly in 2003.
He lives in Camlough, County Armagh with his wife Catherine, his daughter Ăine and his son OisĂn.
He attended St Colman's College, Newry, Queen's University of Belfast (QUB), and the University of Ulster.
In 2001, he contested the Newry and Armagh Westminster seat, coming second to incumbent Seamus Mallon of the Social Democratic and Labour Party (SDLP).
In the Northern Ireland Assembly, he served as the Minister for Regional Development in the Northern Ireland Executive from 8 May 2007 until 16 May 2011.
While on a tour of UK party conferences in autumn 2005, he became the first Irish republican to address the Conservative Party conference and caused controversy by refusing to express regret over the Brighton hotel bombing.In 2011, while Minister for Regional Development, Murphy appointed Sean Hogan, a Catholic, as head of Northern Ireland Water, turning down the applications of four Protestants on the shortlist.
A tribunal subsequently awarded ÂŁ150,000 damages for discrimination to one of these applicants, Alan Lennon, judging that Hogan was appointed because "he was not from a Protestant background and because he was known to the minister and his (then Sinn Fein) ministerial colleagues Michelle Gildernew and CaitrĂona Ruane, who were consulted about the appointment." The tribunal found Murphy's evidence was "implausible and lack[ing] credibility", and that, during Murphy's tenure at the Department for Regional Development, there was a "material bias against the appointment of candidates from a Protestant background".
Murphy disputed the finding which he said branded him "sectarian".
Deputy First Minister of Northern Ireland Martin McGuinness defended him, claiming Murphy doesn't have "a sectarian bone in his body".In December 2012, Murphy appeared as a witness at Belfast High Court in the case of Declan Gormley, whom Murphy had sacked in 2010 from his post as a non-executive director of NI Water.