The investigation into the murder of Robert McCartney has not been delayed by the Police Service of Northern Ireland, according to the McCartney family.
Last week, Sinn Féin's chief negotiator Martin McGuinness criticised the PSNI saying that it could already have arrested two men for the January killing.
Defending the PSNI's performance, Ms Paula McCartney said: "We, as the family, are confident about the PSNI's investigation at this minute."
She was speaking yesterday after members of the family met Taoiseach Bertie Ahern in Government Buildings in Dublin for nearly an hour.
The two men referred to by Sinn Féin were only prepared to admit to the McCartney killing if it was made clear that they had acted "on orders" from the local IRA commander. "They want to go down as Irish volunteers and not as psychopaths," she said, accompanied by her sister, Claire and Mr McCartney's partner, Bridgeen Hagans.
Despite Sinn Féin's public calls on witnesses to come forward, she said the family believed that "intimidation still exists, definitely".
"What is happening is that they are being told what to say, and what not to say, so the full picture is not emerging," she said.
"What has to be remembered is that there was a forensic clean-up. There was intimidation of witnesses. Given all of those facts you can understand why the process is so slow."
The decision by Sinn Féin leader Gerry Adams to call on the IRA to follow a peaceful, democratic path in future would "have no effect on our campaign".
"Our campaign has never been about disbanding the IRA. It is not in our interests to do that. Our only interest is to see the murderers of Robert delivered," Ms McCartney said.
Sinn Féin representatives who were in Magennis's bar in Belfast on the night Mr McCartney was murdered had "a duty to come forward and give evidence".
"They have not done that, and there is still no disciplinary action against those people," said Ms McCartney.
The family is to hold a rally in Dublin shortly. "We believe the people of Dublin do support our campaign, very much so. We believe the people of Dublin would like to demonstrate that support."
The family will hold a vigil outside Magennis's bar next Sunday. "It has never entered our head to give up," she said.
The Taoiseach had assured the family that he would continue to "do everything he can" to bring their brother's killers to justice, she added.
Following the meeting, a Government spokesman said convictions in the case would show doubters that republicans had changed. The Government wanted to "see a decisive breakthrough" in the case and he praised the courage of the family.