US prosecutors have launched a determined bid to uphold Tom and Molly Martens' murder convictions and ensure they serve 20 to 25-year jail sentences for the brutal killing of Irish father-of-two Jason Corbett.
The father and daughter were convicted of battering the Limerick-born businessman (39) to death with a metal baseball bat and a brick in his North Carolina home in August 2015.
Mr Martens (69) is a retired FBI agent while Molly (35), who was Mr Corbett's second wife, suffered from a lengthy history of mental health problems.
North Carolina attorney general officials have now lodged a 96-page submission to the US Supreme Court seeking to have a Court of Appeal ruling overturned and the original second-degree murder convictions upheld.
The shock Court of Appeal ruling on February 4, by a two-to-one decision, granted Tom and Molly Martens a full retrial.
Two judges found that decisions of the trial judge were potentially prejudicial to the defendants and may have undermined their ability to receive a fair trial.
That appeal ruling was immediately challenged by the North Carolina district attorney's office, and the Supreme Court will now rule on either upholding the original conviction or granting a retrial.
Prosecutors have addressed the two key issues which, in the opinion of two Court of Appeal judges, raises concerns about the original trial.
The third appeal judge strongly disagreed and ruled that the trial magistrate, Judge David Lee, had conducted both a fair and rigorous trial.
Now prosecutors have defended Judge Lee's decision not allow into evidence statements taken from Mr Corbett's two children, Jack and Sarah, by social services officials in the days after his killing.
Judge Lee did not allow them because they were directly contradicted by statements made by the children just weeks later on their return to Ireland.
Mr Martens and Ms Martens have both insisted they acted entirely in self-defence that night - despite neither suffering so much as a scratch, cut or bruise at the scene.
In contrast, Mr Corbett's skull was so badly crushed that a pathologist could not count the number of blows inflicted.
The trial heard evidence an attempt had been made to drug Mr Corbett, that he was attacked while asleep in bed and that he was beaten even after he was dead.
It was further stated the father and daughter then delayed ringing for paramedics to ensure Mr Corbett was dead when they arrived.
Judge Lee also did not allow into evidence a statement from Mr Martens in which he recalled an alleged conversation with Michael Fitzpatrick, Mr Corbett's first father-in-law.
This statement was proposed for evidence on the basis it supported the defence case as to Mr Martens' state of mind.
However, it was denied entry into evidence after it emerged that Mr Fitzpatrick, shortly before his death, made a sworn deposition to an Irish solicitor denying that he had ever made any such a statement to the former FBI officer.
It is now expected that the defence teams will respond to the 96-page prosecution report.
A ruling by the North Carolina Supreme Court is not expected for several months, possibly not until early 2021.
Last weekend, Mr Corbett's mother, Rita, who was in her 80s, died in her native Limerick.
Her victim impact statement, at the sentencing hearing of Tom and Molly Martens, was one of the most powerful elements of the 2017 murder trial.