Lawyers for Thomas Martens have filed a motion for his early release over coronavirus concerns.
Mr Martens, 70, and his daughter Molly, were convicted of the second-degree murder of Limerick man Jason Corbett following a trial in 2017.
The pair were sentenced to 20-25 years in prison, but in February they won an appeal against their convictions and a retrial was ordered.
Molly and Thomas Martens remain in prison however, after the Attorney General of North Carolina lodged an appeal against the decision to grant a retrial.
Thomas Martens' lawyer David Freedman told RTÉ News that he has filed a motion for his client's release and that a court date for the hearing has not yet been set.
Mr Corbett, 39, was found dead at his home in North Carolina in August 2015.
His wife Molly and her father Thomas, a former FBI agent, were convicted of his second-degree murder.
Last January, lawyers for the pair told the North Carolina Court of Appeal that they did not get a fair trial and that the trial judge had excluded critical evidence in their case.
They argued statements that Mr Corbett's children had given to social workers should have been allowed as evidence.
They also claimed the jury in the trial had disobeyed instructions from the judge not to have conversations among themselves about the case.
In its ruling in February, the North Carolina Court of Appeal said both defendants were entitled to a new trial.
