The Chief Constable of the PSNI yesterday declined to comment on whether Sinn Fein MLA Conor Murphy will be questioned by police over the murder of Co Armagh man Paul Quinn.
Simon Byrne was grilled at yesterday's Policing Board meeting over the issue by Ulster Unionist MLA Alan Chambers.
Earlier this week Finance Minister Mr Murphy apologised to the Quinn family for branding Paul (21) a criminal and a smuggler, after he was beaten to death by a gang using iron bars and cudgels in a barn in Co Monaghan in 2007.
Significant pressure has been mounting on the authorities to speak to the Newry and Armagh MLA to find out which IRA individuals he spoke to at the time of the Cullyhanna man's death.
Speaking at yesterday's Policing Board meeting, Mr Chambers asked the Chief Constable directly: "Do the PSNI have any current plans to speak with Mr Conor Murphy to seek clarification from him as part of the ongoing investigation or indeed have they received any requests for the Garda Siochana to speak with him on their behalf?"
However, Mr Byrne replied by saying that the PSNI do not comment "as a matter of policy" on any individual witnesses or suspects during investigations as it "wouldn't be fair to do so".
He added that the investigation into Mr Quinn's death is being led by the Garda Siochana and the PSNI will "work at their pace". He added: "They are best placed to determine any further lines of enquiry.
"I don't think there's anything we can add to the public debate as it wouldn't be fair to any of the individuals."
It is understood that a specialist Garda team set up to re-examine the murder will seek to interview Mr Murphy about his claims that the IRA told him they were not responsible.
It is understood that up to 150 potential new lines of enquiry have been identified which will now be pursued by the hand-picked investigation team.
The renewed investigation is due to commence next week following an in-depth year-long examination carried out by the Garda Serious Crime Review Team (SCRT).
Senior security sources have revealed that gardai will make a new bid to interview Mr Murphy.
Mr Murphy has told RTE he is willing to meet the investigating authorities to "discuss any questions that they may have".
It's understood Mr Murphy met investigating gardai by appointment on one occasion after his claims about Mr Quinn's involvement in crime and that he originally agreed to provide gardai with answers to "specific questions" which were deemed important to the investigation.
However, it is also understood that Mr Murphy has not met the gardai since that time.
Conor Murphy has a reputation for being one of the most moderate and reasonable voices in Sinn Fein. He's certainly someone with whom the DUP and the Government find it easy to do business.
There are many compelling reasons why Sinn Fein is unfit to be in government in Dublin, and they have been put forward with increasing eloquence and force since the party started to make huge strides in the polls ahead of Saturday's election.