Lawyers for the PPS have lodged grounds on which they want the Supreme Court to rule on the legal dispute about whether Soldier F should stand trial for two of the killings in Derry 50 years ago.
Dismayed relatives of one of the victims said the development would do little to repair damaged confidence in the PPS.
Thirteen people were shot dead when members of the Parachute Regiment opened fire on civil rights demonstrators in Derry on January 30, 1972.
Another of those wounded died later from their injuries.
Soldier F, who cannot be identified, was formally accused of the murders of William McKinney, 26, and James Wray, 22, plus at least five attempted murders.
But in July last year the PPS announced that all charges against the ex-British paratrooper were to be discontinued.
The case against him was reviewed following the collapse of separate trials against two other military veterans for Troubles-era offences.
Based on an assessment of the admissibility of evidence from the time, it was concluded that the test for prosecution was no longer met.
A legal challenge mounted by Mr McKinney’s family led to the decision being quashed.
In March this year, High Court judges ruled that it “crossed the threshold of irrationality”.
They said the PPS should reconsider the decision taken in a criminal process which has already faced considerable delay.
Committal proceedings against Soldier F were then put on hold to allow time to consider the ruling.
During a review hearing at Laganside Courts in Belfast today, an indication was given that the PPS is now seeking permission to take the case to the Supreme Court.
The process involved lodging questions for the judges to consider whether to grant leave on a point of law of general public importance.
Counsel for the PPS requested a further adjournment to allow time for that application.
District Judge Ted Magill agreed to list the criminal proceedings for mention again in four weeks’ time.
Reacting later, Mr McKinney’s brother Mickey said: “Our family have waited for 50 years for justice for Willie.
“We are disappointed that the PPS could not accept the judgment of three senior judges and just get on with doing its job and prosecuting Soldier F.
“We feel that we have not been treated as victims and this latest step does nothing to repair our damaged confidence in the PPS’ ability or willingness to see this prosecution through to a successful conclusion.”Tags: