Former Det Sgt Owen Corrigan has denied to the Smithwick Tribunal he had information that could have saved an RUC informer's life but failed to pass it on.
At the Smithwick Tribunal,the former garda sergeant said he only had 'general information' and nothing specific that Mr McAnulty was going to be abducted and killed by the IRA.
He said he could not remember if he passed on the detail to the RUC.
He also said Mr McAnulty was not the only one subject to threats at the time.
The tribunal is Investigating whether there was garda collusion in the murder of two RUC officers.
Chief Supt Harry Breen and Supt Bob Buchanan died in an IRA ambush after leaving a meeting in Dundalk Garda Station in March 1989.
Mr Corrigan said the tribunal legal team were unfair in their questioning of him about Mr McAnulty's death.
He had been asked eight times about it while another garda who said he had been told by the IRA that Mr Buchanan was to be shot was not questioned as much.
Mr Corrigan was questioned about evidence given earlier by former British agent in the IRA, Peter Keeley.
The witnesses denied claims he met IRA commander 'Mooch' Blair in a car park or that he he passed any information to the IRA.
He also denied claims by a former member of the British Army's secretive intelligence organisation, the Force Research Unit.
Ian Hurst said a senior officer told him Mr Corrigan was assisting the IRA.
That senior officer denied making the claims when he appeared before the Tribunal.
Mr Corrigan said he believed a former Garda Superintendent, Tom Curran, did got to Garda Headquarters to pass on RUC concerns about him.
However, Assistant Commissioner Eugene Crowley ignored them because he knew them to be false.
It was, the witness said, part of the ploy by the British scurity services to frame him as an IRA mole.
They did this to deflect attention from the collusion in Northern Ireland between themselves and loyalist killer groups like the Glenanne Gang.
The tribunal has now finished until the end of August. It is expected to resume then for several days before coming to a close. A final report is due in October.