A British agent told the Smithwick tribunal in a statement that he heard an IRA member boast about the operation in which two senior RUC men were killed thanks to information supplied through a Garda leak.
Peter Keeley, also known as Kevin Fulton, said that he overheard the conversation in which the boast was made by Patrick “Mooch” Blair.
The statement was referred to by solicitor John McAtamney, who represents Mr Keeley, during his cross examination of a retired RUC Special Branch officer.
Barrister Jim O’Callaghan SC later told the chairman he should have been provided with a copy of Mr Keeley’s statement as it contained allegations against his client.
Mr O’Callaghan represents former detective garda sergeant Owen Corrigan.
Mr Corrigan denies that he ever leaked any information while a garda sergeant, describing it as a “monstrous lie”.
Earlier, the former RUC special branch detective inspector said he was warned not to have any dealings with Sergeant Corrigan in Dundalk when he was assigned to duties near the South Armagh border.
Witness 64, who gave evidence to the Smithwick tribunal from behind a screen to protect his identity, said he was briefed when he was sent to Newry in December 1989 that detective sergeant Owen Corrigan “was not a man I should trust and I should try to have no dealings with him.”
The tribunal was set up to look at claims that a Garda leak may have led to the deaths of RUC chief superintendent Harry Bren and superintendent Bob Buchanan as they returned from a meeting in Dundalk garda station on 2 March 1989.
Witness 64 said he was aware of the two men’s plans to travel south, as he was asked if there were any issues he wanted them to raise during the cross-border meeting, but he did not tell any of his colleagues about the planned trip “because there was no need for them to have that information”.
The witness said he could not remember who had given him the information about Mr Corrigan.
Witness 64 said he was aware of no intelligence that was ever passed on by British agent Peter Keeley (AKA Kevin Fulton) about Mr Corrigan.
And he said that while Mr Keeley had provided “some truthful” information, he also supplied intelligence that was “inaccurate” or “false and misleading”.
Cross examined by lawyers for Mr Keeley, he also agreed that on several occasions Mr Keeley had provided information which had saved lives, and if he had discovered by the IRA he would have been murdered.
Another special branch officer, a former detective constable identified as Witness 65, said he was told to be wary of Mr Corrigan, and recalled that on the one occasion he encountered Mr Corrigan, while speaking with Garda inspector Dan Prenty, the inspector told him to “stop talking”.
Witness 65 said Mr Corrigan entered the room, said nothing, and looked at him closely before leaving.