Career
He was first elected to Dáil Éireann at the 1977 general election and held it until the 1987 general election when he lost it to Brendan Howlin of the Labour Party. He was then elected to the 20th Seanad on the Agricultural Panel. At the 1997 general election, D'Arcy was returned to the 28th Dáil, again unseating Avril Doyle.
In 1981, in Garret FitzGerald's first government, D'Arcy was appointed a Minister of State for Agriculture in the 22nd Dáil. In the 1982–1987 FitzGerald government he was Minister of State for Fisheries until his removal in February 1986 to allow a reshuffle. In 1999, he was elected to Gorey Town Council, and was re-elected at the 2004 local elections, and retired in 2009.