The former Dundalk garda who was accused by Jeffrey Donaldson of colluding with the IRA has said that the DUP MP was trying to set him up so he would suffer the same fate as Pat Finucane.
Owen Corrigan told the Smithwick Tribunal that he was set up by the IRA and "organs of the British government".
The tribunal is investigating whether Mr Corrigan and other former gardaí, Leo Colton and Finbarr Hickey, passed information to the IRA which resulted in the deaths of two senior RUC officers.
Chief Supt Harry Breen and Supt Bob Buchanan died in an IRA ambush just minutes after leaving a meeting in Dundalk Garda Station in March 1989.
Mr Corrigan was named by Mr Donaldson in the British Houses of Parliament as a member of the gardaí who passed information to the IRA about the visit. That is a claim that Mr Corrigan has always disputed.
The former detective sergeant is in the witness box for the second day today.
He said that Irish governments had been putting pressure on the British governments to hold a public inquiry into the death of Pat Finucane.
However, as part of their response, “organs of the British Government” identified him as an IRA mole to deflect attention from what their involvement in the killing of Mr Finucane.
He pointed out that another MP had named Mr Finucane as an IRA sympathiser under parliamentary privilege, and the solicitor was later shot dead by loyalists in front of his family.
"Mr Donaldson set out to achieve the same," Mr Corrigan claimed. "I was in a very, very vulnerable position given where I was living."
Mr Corrigan also said the IRA wanted him out of the way because he was so successful against them.
"I was the meat in the sandwich," the witness told the tribunal.
Rumours, he said, had been the biggest problem of his career. Rumours had been started by people who contributed nothing else to society.
He was asked by Justin Dillon, Counsel for the tribunal, why he opted out of work when the new regime took over An Garda Síochána.
The witness said that he was "the most successful officer ever", but he was then saddled with four officers who knew nothing. Mr Corrigan said he could not work with people like that.
He was asked about the public affected by crime, to which he responded: "I never investigated ordinary crime. I was dealing with the most dangerous elements in the society. I had done more than enough without any appreciation."
The witness was also asked why he had no dealings with Chief Supt John Nolan in Dundalk.
Mr Corrigan said it was up to him to "come to me and avail of my many qualities. I was the jewel in the crown.”
His evidence is continuing.