At the 1992 Irish general election, Upton stands again in Dublin South-Central, and in Labour’s “Spring Tide” surge at that election, he tops the poll with nearly 12,000 first-preference votes, a remarkable 1.48 quotas. He is re-elected at the 1997 Irish general election with a considerably reduced vote.
In the 28th Dáil Upton is appointed as Labour’s spokesperson on Justice, Equality and Law Reform. A leading critic of Labour’s 1999 merger with the Democratic Left, he nonetheless becomes the party’s spokesman on communications and sport after the merger.
Upton dies suddenly of a heart attack on February 22, 1999 at the UCD Veterinary College, where he is an occasional lecturer. He is taken to St. Vincent’s Hospital and his death is officially confirmed. He is survived by his wife and their four children. Politicians of all parties pay glowing tributes to him for his outspoken but “erudite and incisive” contributions to politics and to Irish culture.
The by-election for Upton’s Dáil seat in Dublin South-Central is held on October 27, 1999, and won for the Labour Party by his sister Mary Upton.
Following Upton’s death, the University College Dublin branch of the Labour party is named in his honour due to his involvement with the college. It has since been renamed to honour the Spanish Civil War veteran Charlie Donnelly.
After serving for four years on the Roscommon County Council, Doherty is elected as a Fianna Fáil TD for the Roscommon–Leitrim constituency at the 1977 general election.
Doherty’s brother-in-law, Garda Thomas Nangle, is charged with assaulting James McGovern, a native of County Fermanagh, in a public house in December 1981. On September 27, 1982, hours before the case is due to be heard in District Court in the small village of Dowra, County Cavan, McGovern is arrested by the Special Branch of the Royal Ulster Constabulary (RUC) on the basis of entirely false Garda intelligence that he is involved in terrorism. The case against Nangle is dismissed because the principal witness, McGovern, fails to appear in court. The solicitor representing Nangle is Kevin Doherty, Seán Doherty’s brother. This questionable use of Garda/RUC Special Branch liaison, set up under the 1985 Hillsborough Anglo-Irish Agreement, prevents meetings between the Garda commissioner and the RUC chief constable for almost three years.
After Doherty leaves office it is revealed in The Irish Times that he ordered the tapping of three journalists home telephones. The newspaper also discloses that he has been interfering in the workings of the Garda and the administration of justice for both political and personal reasons. He immediately resigns from the party only to rejoin it in 1984.
At the 1989 general election his loses his seat in Dáil Éireann to the independent candidate Tom Foxe. He is also an unsuccessful candidate in the elections on the same day to the European Parliament, but he is later elected instead to the Seanad on the Administrative Panel and becomes the Cathaoirleach (Chairman) of the 19th Seanad.
In January 1992 the phone tapping scandal returns to haunt Fianna Fáil. Doherty announces in a television interview that he had shown transcripts of the conversations to Charles Haughey while Haughey was Taoiseach in 1982 although he had previously denied this. Haughey denies the claim also, but is forced to resign from the government, and then resigns as leader of Fianna Fáil. Doherty then regains his seat at the 1992 general election and holds it until his retirement at the 2002 general election.