Lawyers for Molly Martens-Corbett and Thomas Martens have filed court papers in the US calling for their guilty verdicts to be thrown out and a new trial established, according to the District Attorney for Davidson County.
Speaking to RTÉ News, DA Garry Frank said that the motion was filed "late yesterday afternoon".
He said: "We do not believe that the motion has any merit. We will review it and it will be up to a judicial official to make a decision."
The lawyers allege that some jurors engaged in misconduct and bias, which they say requires that the verdict be set aside.
They said a judge should schedule an evidentiary hearing, set aside the jury's verdict and grant the two a new trial.
Mr Frank said his office would "file appropriate response on it", after which it "will have to be heard by the trial judge, who will make a decision whether to have a hearing, and if so what kind of hearing."
He said he expected the matter to be concluded "within 30 days".
Mr Frank also confirmed that this process is entirely separate to the appeals process.
Earlier this month, a jury found Martens-Corbett and her father guilty of the second-degree murder of Irish man Jason Corbett two years ago.
Second-degree murder is defined as an intentional killing that was not premeditated.
Both Martens-Corbett, who was married to Mr Corbett, and her father had pleaded not guilty, claiming self-defence.
Mr Corbett, 39, was killed in his home in Wallburg, North Carolina on 2 August 2015.
