Sinn Féin president Gerry Adams has vowed that those responsible for the killing of Robert McCartney will be made to "account for their actions".
In a keynote address to his party's ardfheis in Dublin this evening, Mr Adams described the murder of the Belfast father of two as a "huge issue" for the party and said those responsible should admit to what they did in a court of law.
"This is the only decent thing for them to do," he told an audience which included members of the murdered man's family who had accepted an invitation to attend the ardfheis earlier in the day.
Mr Adams described the family's call for justice and truth as a "just demand" and pledged his party's support.
The family were at the ardfhies in the RDS at his invitation, he said, because he wanted to demonstrate Sinn Féin was "on their side".
He said: "I am not letting this issue go until those who have sullied the republican cause are made to account for their actions".
Under increasing pressure to prove his party's commitment to end paramilitary violence in the wake of recent events, the Sinn Féin leader said there was no place in republicanism for anyone involved in criminality.
He said: "Our detractors will say we have a particular view of what criminality is."
"We have not. We know what a crime is both in the moral and legal sense, and our view is the same as the majority of people. We know that breaking the law is a crime," Mr Adams said.
But significantly he said Sinn Féin refuses to criminalise those who break the law in pursuit of "legitimate political objectives".
He singled out the Minister for Justice, Michael McDowell, as leading an invective against Sinn Féin and claimed the Government "deeply resented" his party's successes.
Mr Adams claimed the Minister had stepped into the shoes of Margaret Thatcher in attempting to criminalise Sinn Féin but that he would not succeed.
Mr Adams said he accepted the word of the IRA when it denied involvement in last December's Northern Bank raid. "The truth is that no one knows at this time who did the robbery, except the people involved.
"Martin McGuinness and I were accused by the Taoiseach of having prior knowledge. That is untrue," the Sinn Féin president said.
He said the governments were seeking to reduce all of the issues to one - that is the issue of the IRA - even though they know the IRA is not the only issue. Mr Adams said Sinn Féin's leadership was working to create the conditions where to IRA ceases to exist.
But he warned the IRA cannot be "wished away, or ridiculed or embarrassed or demonised or repressed out of existence."
