The body that monitors paramilitary activity has said the IRA was not responsible for beating a 21-year-old man to death in Monaghan last year.
Paul Quinn died after being lured to a cattle shed and beaten with iron bars and pick axe handles by masked men.
The IMC said the killing was "clearly contrary to the instructions and strategy of the IRA leadership".
It said it was the result of local disputes and some members, or former IRA members, may have been involved.
However, the commission said there was no evidence that the IRA leadership was linked to the incident.
Mr Quinn's parents said their son had been threatened by members of the IRA in south Armagh.
Sinn Féin said there was no IRA involvement and condemned the murder.
In a statement on Thursday, the party said: "It says much of the conspiracy theories which have been put forward by the political opponents of Sinn Féin linking the IRA to this horrific killing that even a body like the IMC cannot bring itself to give them any credibility."
Secretary of State Shaun Woodward said he welcomed the assessment that the IRA remains committed to a political path.
He also called on loyalist paramilitary groups to begin the process of decommissioning weapons.
Lord Alderdice speaking at the launch of the report
"The IMC has reported that PIRA remains committed to, and does not believe it will be diverted from, the political path which it has followed for a number of years and that republicans are engaging with the policing institutions and encouraging the reporting of crime in their areas," Mr Woodward said.
In a statement, he said the group welcomed statements by the UVF last May and one by the UDA in November, saying they were putting weapons beyond use.
"However loyalists will be judged on their actions and not just their words and it is clear that more needs to be done, including the decommissioning of weapons."
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