PSNI assistant chief constable Drew Harris attended the Smithwick Tribunal under tight security today.
Mr Harris joined lawyers for the PSNI but did not take the stand or give evidence. He was present when details of Garda cover for visits to the Republic by Northern VIPs during the 1980s were being discussed.
The tribunal is inquiring into allegations that members of the gardaí or other employees of the State colluded with the IRA in the 1989 killing of RUC officers Harry Breen and Bob Buchanan.
The two men were killed in an ambush in south Armagh minutes after leaving a meeting in Dundalk Garda station.
During this morning's hearing, a former detective garda who served most of his career in Dundalk said he had never heard or seen of evidence of an IRA mole in the station.
Patrick O'Connor told told counsel for the PSNI Mark Robinson he had travelled on VIP escort duty on a number of occasions, sometimes in the company of Det Sgt Owen Corrigan, another member of the gardaí based in Dundalk. Mr Corrigan is represented at the tribunal.
Mr O'Connor said he was aware Mr Corrigan had a reputation for not paying people. He said that his only financial dealing with the sergeant was when he loaned him £10 while escorting the Northern Irish secretary of state to a rugby match at Landsdowne Road. On a following occasion when he was escorting then RUC chief constable Sir Jack Hermon, Mr Corrigan paid back the loan.
Mr O'Connor told Mr Robinson that on one occasion he prepared a report after a detective unit car he was responsible for was damaged. Mr Corrigan was subsequently investigated for failure to report an accident.