The best-known surveillance case in recent times involved the journalists Ms Geraldine Kennedy, then of the Sunday Tribune, and Mr Bruce Arnold, of the Irish Independent.
Both had their phones tapped during the short life of the 1982 Fianna Fail government. Ms Kennedy had been writing about challenges ail to Mr Charles Haughey's leadership, and official surveillance was authorised by the then minister for justice, Mr Sean Doherty.
The case ended in the High Court in January 1987, when both were awarded £20,000 in damages. Mr Arnold's wife Mavis, also a journalist, was awarded £10,000. In his judgment, Mr Justice Hamilton said the State's action against the three was "an attack on their dignity and freedom as individuals and cannot be tolerated in a democratic society".
The journalist Mr Vincent Browne also had his telephone tapped between 1975 and 1983. A legal action by him against the State ended in 1995 with a private settlement of £91,000. Although the surveillance was explained on the basis of Mr Browne's journalistic contacts with the IRA, he later discovered that of 85 transcripts of his conversations, only four related in any way to subversives.
In 1995 the minister for transport, energy and communications, Mr Michael Lowry, claimed his efforts to break up a "cosy cartel" in the semi-State sector had made him the centre of a "sinister" surveillance operation. There was a Garda investigation, but Fianna Fail later called the allegations "bogus".
Later that year, a Fianna Fail TD reported a man with a video camera outside his house while he was meeting the three businessmen at the centre of the so-called Lowry affair. Mr Martin Cullen said his wife had seen the man but he ran off when he saw her.