A report into one of Northern Ireland's worst terrorist atrocities should be quashed due to alleged serious oversights, the High Court heard today.
Victims' relatives are challenging the findings from a review by the now defunct Historical Enquiries Team of the original police investigation of the McGurk's Bar massacre.
Fifteen people were murdered when the north Belfast pub was blown up by loyalist paramilitaries in December 1971.
Four years ago a Police Ombudsman probe identified investigative bias in how the RUC handled the case.
It concluded that police failed to properly probe loyalist responsibility for the bombing because they were so focused on the idea that the IRA was to blame.
At the time of the bombing it was suggested that it may have been an accidental "own goal".
But in a subsequent review the HET reached a different conclusion - claiming no evidence of any bias on the part of the RUC investigators.
Those findings are now being subjected to a judicial review taken by Brigid Irvine, whose mother Kathleen was among the 15 people killed in the attack.
In court today counsel for the Chief Constable argued that the case should not proceed to a full hearing.
Peter Coll QC contended that Article 2 right to life provisions under the European Convention on Human Rights were not engaged because the HET was carrying out a review rather than a full investigation.
The re-examination had identified further evidential opportunities which were then transferred to the PSNI's serious crime branch, he stressed.
Just one man has ever been convicted for his part in the attack.
Mr Coll also questioned the point in pursuing a challenge against the findings of a body no longer in operation.
"This is simply an attempt to litigate a difference in opinion between two state agencies," he said.
But at one point Lord Justice Gillen asked if he "dancing on the head of a pin" in contending that the review was not part of an overall investigative process.
The judge also outlined Ms Irvine's allegation that the HET "completely ignored, overlooked or deliberately set aside" relevant considerations.
"I still have some difficulty in seeing why (alleged) cover-up, oversight or whatever could not attract Article 2 aspects," he added.
Adjourning the case, Lord Justice Gillen requested further submissions on the points in contention.
But in a pledge to victims relatives in the courtroom, he said a further hearing will take place before the end of term.
"I can assure the applicant, relatives and those genuinely concerned with this case that it will be heard with haste," he added.
Outside court Ms Irvine's solicitor, Paul Pierce of KRW Law, insisted the HET report should be quashed.
"This is part of an historical narrative surrounding the conflict, and the applicant is determined that the facts about the McGurk's Bar bombing, which include the investigation at the time and subsequent review, should be scrutinised by the courts," he said.
"Throughout the course of the HET investigation the family members of victims presented them with important and significant information that would have assisted them, including official documents from the Public Records Office here in Northern Ireland.
"None of these were considered or acknowledged in the body of the report, so it calls into question the independence of the HET investigation."