The revelations were made by DUP MEP Jim Allister who also challenged three men at least two of them Sinn Féin members to come forward with evidence of the night's horrific events.
Sinn Féin's two MEPs, Bairbre De Brun and Mary Lou McDonald, sat quietly in the parliament as speaker after speaker described and condemned the horrific details of the Belfast man's murder last January.
Two of his sisters, Catherine and Paula, sat in the visitors' gallery as their courage was praised and support and funding for their campaign was promised by the political groups.
But the DUP's sole MEP, Jim Allister, held everybody's attention as he named names and blamed Sinn Féin for the murder of the 33-year-old father of two.
"By a hand signal, indicating a knife should be used, a member of the IRA's Northern Command gave the order to kill and a key Sinn Féin member savagely wielded the knife and butchered this innocent man, before multiple witnesses.
"An IRA unit, led by the volunteer who had fetched and then disposed of the knife, then co-ordinated a clean-up operation to destroy forensic and real evidence, including CCTV footage. Then, in classic IRA style, the intimidation brigade swung into action to silence the witnesses.
"Though the IRA and Sinn Féin claim to have expelled or suspended up to 10 members linked to this murder, their duplicity and double-dealing is amply illustrated by the fact that three months after the murder this cut-throat killer
remained publicly proclaimed as one of Sinn Féin's official treasurers and the man who ordered the killing still struts the streets of Belfast in the company of the IRA's Chief of Intelligence, Bobby Storey and leading Provo, Eddie Copeland."
Dublin MEP Mary Lou McDonald said it was irresponsible of Mr Allister to name names as it could jeopardise a trial.
She said Sinn Féin was not involved in the murder.