The appeal by Ian Bailey against his extradition to France in connection with the murder of French film-maker Sophie Toscan Du Plantier is being heard at the Supreme Court today.
On Friday, the five judge Supreme Court ruled new material provided by the State last November to Mr Bailey's lawyers, including a 44-page critical review of the conduct of the murder investigation and outlining the reasons why the former DPP decided not to prosecute him, admissible evidence in the appeal.
The court rejected arguments on behalf of the State that the material was nothing new and not relevant and noted the Chief Prosecution Solicitor had informed Mr Bailey's lawyers in a letter last November that the Attorney General had advised the Minister for Justice the material was "very significant".
The Minister for Justice had also stated it was in the "interests of justice" that the material be disclosed, the court heard.
In those circumstances, Mr Justice Adrian Hardiman remarked he could not see how the State was contending the material was not relevant or admissible.
Martin Giblin SC, for Mr Bailey, said the case had now become "unique" in the circumstances in which the material has become available.
As a result of the material, his side now knew the decision by former Director of Public Prosecutions Eamonn Barnes not to prosecute Mr Bailey was firmly rooted in his view there was "no evidence whatsoever" against Mr Bailey.
The material also showed the then DPP was firmly of the view the Garda investigation into the murder was prejudiced and biased and this, he submitted, would have greatly strengthened his side's argument the French extradition warrant was tainted.
After hearing arguments from both sides, the five judges adjourned to consider a motion by Mr Bailey to have the material admitted as new evidence.
Mr Giblin had also sought the material be dealt with in a fresh High Court hearing.
After considering the matter, Chief Justice Ms Justice Susan Denham said the court had decided the material should be admitted as new evidence in the Supreme Court appeal hearing, which is fixed to open on Monday.
The court would give its reasons for that decision later in a written judgment, she said.
Mr Bailey, who was in court today, is wanted for questioning by an investigating judge in France in connection with the death of Ms Toscan du Plantier.
The body of the 39-year-old film maker was discovered near her holiday home in Schull, Co Cork, on December 23rd, 1996.
Mr Bailey has always denied any involvement in the murder. He was arrested by investigating gardaí and the DPP found no basis to charge him.
In March, the High Court ruled against Mr Bailey's challenge to his extradition and he then appealed to the Supreme Court.
His lawyers last month said they wished to have the case re-heard in the High Court having examined the material provided to them by the State in November.
Mr Bailey's side argued that material disclosed a "breathtaking" level of wrongdoing by State officials and, had it been available to them during the High Court hearing, they would have been able to make "a much stronger case" concerning allegations of Garda misbehaviour in the murder investigation.
