Real IRA leader Micheal McKevitt today lost his appeal against his conviction for directing terrorism.
McKevitt (54), from Beech Park, Blackrock, Co Louth, was jailed for 20 years by the Special Criminal Court in 2003.
At the Court of Criminal Appeal today Mr Justice Nicholas Kearns said the court was satisfied that the Special Criminal Court was entitled to conclude that the main prosecution witness, FBI agent David Rupert, was a credible witness and to accept his evidence.
The judge added that the court was also satisfied that all matters relating to the disclosure of documents had been properly dealt with.
McKevitt was the first person to be convicted in the State for the offence of directing terrorism, which was introduced after the Real IRA bomb attack in Omagh in 1998 in which 29 people died.
McKevitt also received a six-year concurrent prison sentence for membership of an illegal organisation that the court said was the Real IRA.
The four-day appeal last month centred on issues related to the reliability of Rupert, who had infiltrated the Real IRA and attended Real IRA army council meetings at which, he said, McKevitt was present.
Senior counsel Michael O'Higgins, for McKevitt, argued that Mr Rupert was "a deeply avaricious man" who had been paid $1.4 million by the FBI and £400,000 by the British Security Service.
He also said Rupert was a lifelong criminal who had been involved in smuggling drugs, contraband, people and explosives.
Mr O'Higgins argued there was no full and proper disclosure of all material relating to Rupert and that the Special Criminal Court had erred in law by not adequately assessing Rupert's credibility as a prosecution witness, despite his history of involvement in criminality.
But, opposing the appeal, George Birmingham, SC for the State, said Rupert had performed the tasks he had agreed to do with "remarkable skill, resourcefulness and courage", which had "served all the people of this State".