The murder of a man nine days ago has cast more doubt over Sinn Féin's suitability to be in government, it was claimed today.
Even though senior Sinn Féin leaders such as Gerry Adams have strongly denied IRA involvement in the murder in the Republic, Democratic Unionist chief whip Lord Morrow claimed that most people believed republican gangsters were responsible.
In the hardest hitting statement on the murder yet by a senior DUP figure, he challenged republicans to show their condemnation of the murder was sincere by disbanding the IRA Army Council.
"The murder of Paul Quinn casts further doubts over Sinn Féin's suitability for government," the Fermanagh and South Tyrone MLA said.
"There is little doubt in anyone's mind that republican gangsters were involved in this horrendous and brutal murder.
"While it bears all the hallmarks of the Robert McCartney murder and while Sinn Féin continue to refuse to call for the disbandment of the IRA Army Council, the finger of suspicion will always be pointed in their direction."
Unionists have expressed unease at allegations that a Provisional IRA gang lured Mr Quinn over the border with the Republic and beat him to death at farm buildings at Tullycoora near Oram in Co Monaghan.
Mr Quinn's family alleged he was attacked after becoming embroiled in a dispute with local IRA members.
If a firm IRA link is established in the police investigation taking place on both sides of the border, it would undoubtedly put pressure on the power sharing executive which has been operating in the North since May involving the Ian Paisley's Democratic Unionists and Sinn Féin.
Senior Sinn Féin figures have condemned the murder, have said they believe it was carried out by criminals and have linked it to fuel smuggling.
Up until now, senior DUP politicians have been cautious about attributing the attack.
Deputy leader Peter Robinson claimed at the weekend he did not believe it was centrally ordered by the IRA.
However Lord Morrow expressed concern today that a lack of co-operation from republicans would frustrate police efforts to bring those responsible for killing Mr Quinn to justice.
"If Sinn Féin is to be taken seriously as a democratic party they must demonstrate in a transparent way their unqualified support for the police," the DUP peer said.
"Words are not sufficient. Actions speak considerably louder.
"The police in turn must reassure the public that they will leave no stone unturned to find the culprits of this foul murder. They have much more to do in this instance.
"The police must not consider the political consequences and only a full disclosure will gain the confidence of the public at large."
Lord Morrow said he feared a synthetic condemnation of the murder by Sinn Féin would be the best anyone could hope for.
"The acid test for Sinn Féin is, if you are sincere in your condemnation this must be followed through with the standing down of the IRA Army Council," he continued.
"This is something which is within Sinn Féin's control. Sadly at present this looks highly unlikely to happen.
"The devolution of policing and justice next spring is but a pipe dream. With murders such as the Paul Quinn case and the lack of cooperation from Sinn Féin for 'on-the-ground' policing, the confidence of the community is at an all-time low."