Protected witness Mr Russell Warren denied at the Special Criminal Court today that he was "telling lies" to the court about his account of the events surrounding the murder of journalist Veronica Guerin.
He denied suggestions by counsel for Mr John Gilligan, who is on trial for Ms Guerin's murder, that he "can't tell the truth" and is "telling lies."
Mr Warren admitted under cross examination by defence counsel Mr Terence McDonald QC , that gardai had found some cannabis during a search of his house in 1997 but he said no heroin had been found there.
Mr Warren admitted that he had never been interviewed about the cannabis which he said was found in his wife's jewellery box.
Warren also told Mr McDonald that he went to Naas on the morning of the Guerin murder to look for a red Opel Calibra car around the courthouse.
He said he parked his van and went to the social welfare office in the town but was unable to point out to Mr McDonald on a map supplied by the defence the exact location of the office.
Warren said that he also asked a uniformed garda for directions to the courthouse and then drove past it and parked his van somewhere else before going back to look for the red car.
He said he saw the red car pulling out into traffic just after he bought a newspaper and soft drink in a shop. He said he the car pulled into the traffic and headed towards Dublin.
Warren said he could not see the driver and only saw "somebody small behind the headrest."
Warren has previously told the court that he stole the motorbike used in the murder and that he witnessed the pillion passenger on a motorbike fire the fatal shots into Ms Guerin's red Opel Calibra car.
He has also given evidence that he was in constant contact by mobile phone with the accused before and after the murder.
It was the fifteenth day of the trial of John Gilligan (48), with addresses at Corduff Avenue, Blanchardstown, Dublin; Jessbrook Equestrian Centre, Mucklon, Enfield, Co Kildare; and HM Prison Belmarsh, London, who has pleaded not guilty to the murder of Sunday Independent crime reporter Veronica Guerin(37) at Naas Road, Clondalkin, Dublin on June 26th, 1996.
Gilligan also denies fifteen other counts alleging the importation of cannabis and firearms and ammunition offences.
The prosecution has claimed that John Gilligan was "in control and command" of a criminal gang that imported and distributed large amounts of cannabis and that he organised the murder of Ms Guerin. The trial is continuing.