The father of an IRA murder victim is taking legal action in a bid to secure a fresh inquest amid claims a top British agent was involved in the killing.
Frank Mulhern is seeking a High Court ruling that the Attorney General must direct a new probe of the circumstances surrounding the death of his son Joseph in 1993.
The legal challenge is based on allegations that the Army’s most prized asset within the Provisionals, who operated under the codename Stakeknife, played a central role in the murder.
A judge is now set to hear the challenge alongside separate proceedings brought by the family of an IRA man shot dead by the RUC in 1991.
Relatives of Colum Marks want the Police Ombudsman to be ordered to examine a killing also allegedly linked to a state agent.
Lawyers involved in both cases contend there is obligation to investigate under Article 2 of the European Covention on Human Rights.
Joseph Mulhern, 23, was abducted, interrogated and shot by the IRA, who accused him of being a police informer.
His body was dumped on a remote hillside near Castlederg, Co Tyrone.
With no-one ever convicted of the murder, the victim’s father is seeking to judicially review a decision to refer the case to the Director of Public Prosecutions.
Papers lodged as part of the case claim the police have been aware of evidence that Mr Mulhern was killed “by or at the instigation of a British agent, Freddie Scappaticci”.
West Belfast man Scappaticci left Northern Ireland in 2003 when he was named in the media as being Stakeknife.
Before quitting his home, however, he vehemently denied being the agent who allegedly headed up the IRA’s internal security unit, known as the ‘nutting squad’.
In October last year Director of Public Prosecutions Barra McGrory QC called for police to examine Stakeknife’s activities, along with what was known by RUC Special Branch and MI5.
Chief Constable George Hamilton has since decided detectives from an external force should handle an inquiry which could last five years and cost up to £35 million.
Legal papers featuring in Frank Mulhern’s case claim there is no realistic prospect of a prosecution.
They state: “Scappaticci is believed to have joined a witness protection programme and be living under an assumed name.
“In all the circumstances there is no realistic prospect of the DPP and/or the PSNI conducting any investigation which will uncover links between the State and the murder of the deceased so that everyone concerned will be held accountable and lessons can be learned.”
Separate proceedings have now also been brought in a bid to compel the Police Ombudsman to investigate the shooting of Colum Marks.
The 29-year-old IRA man was fatally wounded when police opened fire during an attempted mortar attack on security forces in Downpatrick.
His relatives claim the RUC operated a shoot-to-kill policy.
In court on Tuesday counsel for the family contended there was material to suggest a state agent was involved.
Their challenge is to regulations governing the Ombudsman’s office preventing it from probing a case where there has already been a police investigation.
Mr Justice Maguire confirmed he will hear arguments in both challenges together later this month.