MURDERED Belfast lawyer Pat Finucane was the victim of an army-run death squad normally associated with Latin American dictatorships, the Court of Appeal has heard.
Counsel for the solicitor's widow claimed his assassination was due to covert, state-sponsored terrorism and represents a "horror story" for the British Government.
The allegations were made as Geraldine Finucane began her bid to overturn a ruling that Prime Minister David Cameron acted lawfully in refusing to hold a public inquiry into the killing.
But the challenge was dramatically adjourned on Monda after it emerged that one of the three appeal judges had been involved in a separate civil action she issued more than 20 years ago.
Mr Finucane was gunned down by loyalist at his home in north Belfast in February 1989.
His family have campaigned for a full examination of alleged security force collusion with the killers. Mrs Finucane took the Prime Minister to court after he ruled out a public inquiry in 2011.
Instead, Mr Cameron commissioned QC Sir Desmond de Silva to review all documents relating to the case and produce a narrative of what happened.
That report confirmed agents of the state were involved in the murder and that it should have been prevented. However, it concluded there had been no overarching state conspiracy.
The Finucane family rejected the findings and accused the government of unlawfully reneging on previous commitments.
Pledges to set up such a tribunal, based on the recommendation of retired Canadian judge Peter Cory, were made by a former Labour government in 2004 and reaffirmed in the following years, it was contended.
Last year a High Court judge ruled that Mr Cameron acted lawfully in refusing to hold a public inquiry.
He found that Mrs Finucane had received a clear and unambiguous promise of an inquiry, but backed the Government's case that other public interest issues, including political developments in Northern Ireland and the potential financial pressures of a costly inquiry, were enough to frustrate her expectation.
Despite throwing out Mrs Finucane's legal bid the judge also said the State has not fully met its human rights obligation to investigate.
Opening an appeal against that verdict, Barry Macdonald QC claimed the case was about an abuse of power.
He said the 500 page de Silva report, which highlighted the connection of law enforcement elements to the murder conspiracy, contained only five pages on the role of the Government.
Referring to Ken Barrett, the loyalist gunman convicted of the killing, Mr Macdonald said: "The only person held accountable was one of the UDA puppets used to pull the trigger."
He quoted correspondence from one of Mr Cameron's closest advisers which described the killing as far worse than anything alleged in Iraq or Afghanistan while another described the Finuncane case as "something of a horror story for the security forces".
Questioning why the authorities appeared to regard the murder as the most difficult from the Troubles, the barrister continued: "The answer is because in this liberal democracy where the rule of law is supposed to be paramount, the army is running death squads of a kind normally associated with Latin American dictatorships of the era."
Investigations into the assassination carried out by former Scotland Yard chief Sir John Stevens was obstructed at the highest levels of the army and RUC, it was claimed.
He claimed that commissioning the de Silva review instead of a full public inquiry insulated government ministers from any further scrutiny.
However, the planned three-day hearing had to be adjourned after counsel for the Governmen applied for Lord Justice Weir to recuse himself after it emerged that while a barrister in the early 1990s he had endorsed a writ issued by Mrs Finucane in a civil action over her husband's killing.
Proceedings were adjourned until November.
