THE family of the only prison officer to be assassinated in the Republic believe they know the identity of his killer after new evidence came to light in recent weeks.
Former Portlaoise chief prison officer Brian Stack's children will tomorrow ask Sinn Fein leader Gerry Adams to pressure senior party colleagues to confess anything they know about the murder 30 years ago.
The father of three was shot in the back of the neck on March 25, 1983, on a busy Dublin street after leaving a boxing contest at the National Stadium.
Paralysed and brain-damaged from the shooting, he suffered for a further 18 months before dying from his injuries at the age of 47.
Austin Stack, who followed in his father's footsteps and is now assistant governor of Dublin's Wheatfield Prison, said he will be asking Mr Adams to use his influence to help secure an IRA admission and apology.
"I am confident I know the identity of the killer and the identity of the individual who sanctioned it, and I want Gerry Adams to talk to his organisation and try to get people who know something to talk to us," he said.
Mr Stack has been gathering evidence from a number of sources on his father's murder over recent years.
But he said corroborating evidence received in the last month has convinced him of the identities of the gunman, his getaway motorcycle driver and the man who sanctioned the killing within the IRA leadership.
His family have now ruled out any possibility of organised crime gang involvement in the shooting.
They are certain their father was assassinated because of the strict security regime he implemented at Portlaoise, which housed all republican prisoners at the time.
"I'm led to believe he organised searches quite regularly, he changed locks once a month - the Provos had no peace with him when he was there," said Mr Stack.
"He was determined the security of the prison wasn't going to be breached on his watch."
Mr Stack said his father was aware of plans for an IRA prison escape - an attempted break-out failed in 1985 - and thought there may have been insiders in cahoots with the Provos.
The prison officer chief had confided in a colleague that he had stumbled upon something, that if proven, would rock the State to its foundations.
Mr Stack said an IRA plan was hatched to remove his father from the prison.
"It was an act built out of vengeance and frustration," he said.
"The Provos could not do what they wanted to do down there and they needed to get my father off the scene."
An advocate of restorative justice, Mr Stack said he would like to eventually meet his father's killer.
"I would let the individual know the effects on my family, my mother and brothers - and even my children who never met their grandfather - and let them know the effect of what they did," he said.
"I would also ask them to explain to me why they did it, and how they are feeling about that now."
Both he and his brother Oliver will meet Mr Adams in Leinster House tomorrow evening.
The Sinn Fein leader has already told the Stack family not to raise their expectations that he or the Sinn Fein leadership can help with their particular requests.
But he said he would do whatever was in his power to help them find closure.
"I don't know whether Gerry Adams can tell us who carried out the murder," he said.
"Gerry Adams had connectivity with an organisation that carried out a lot of murders and I don't know if he will bring to the family any information that isn't presently either available to the family or An Garda Siochana.
"But I do know that the appalling murder of Brian Stack has been re-investigated by An Garda Siochana."
Mr Shatter said he did not yet know the outcome of the re-investigation but understood it was ongoing.