A defence counsel for Mr John Gilligan, accused of the murder of Veronica Guerin, said yesterday that the protected witnesses in the trial were "compromised witnesses".
Mr Michael O'Higgins SC told the Special Criminal Court that the Witness Protection Programme was controversial and a similar system known as "supergrass trials" had run in Northern Ireland in the 1980s before eventually collapsing.
Mr O'Higgins said he would not use the description "super grasses" or "protected witnesses", but he thought a fair description was "compromised witnesses".
He said the relationship that existed between these witnesses and the State was such that the witnesses were "utterly compromised".
"It threatens to compromise the entire criminal justice system as we understand it," he added.
Mr O'Higgins said that a decision had been taken by senior members of the gardai backed up by the Minister for Justice and with the approval of the Director of Public Prosecutions, whereby the witnesses would not be prosecuted for serious crimes, would be protected and would receive financial benefits and concessions such as temporary release from prison.
Mr O'Higgins was making the closing defence submissions on the 42nd day of the trial. Mr Gilligan (48), with addresses at Corduff Avenue, Blanchardstown, Dublin; Jessbrook Equestrian Centre, Mucklon, Enfield, Co Kildare; and HM Prison Belmarsh, London, has pleaded not guilty to the murder of Sunday Independent crime reporter Veronica Guerin (37) at Naas Road, Clondalkin, Dublin, on June 26th, 1996.
Mr Gilligan also denies 15 other counts alleging the importation of cannabis and firearms and ammunition offences. The prosecution has claimed that Mr Gilligan was the leader of a drugs gang and played a leading part in a pre arranged plan to shoot Ms Guerin.
Earlier Mr O'Higgins said that protected witness Charles Bowden's evidence did not "pass muster". He submitted that the court should "effectively disregard" everything Bowden told the gardai since March, 1997, and he said the court should not even consider Bowden's evidence.
The defence submissions continue today.