THE Government should trawl its documents archive to support the family of a solicitor murdered by Northern Ireland loyalists with state support, it was claimed.
The department of the Taoiseach Enda Kenny and other key government organisations should examine its files anew in an attempt to help the family of Pat Finucane, Sinn Fein president Gerry Adams said.
British police and Army agents inside Northern Ireland's largest loyalist political gang, the Ulster Defence Association, had a key role in assassinating the north Belfast lawyer, a report from former UN war crimes investigator Sir Desmond de Silva said this week.
The Taoiseach has already reiterated his support for a full public inquiry into events surrounding the 1989 killing.
Mr Adams said: "The Irish Government needs to shift into a higher gear in support of the family."
Mr Finucane, 38, was shot dead at his north Belfast home in February 1989 in front of his wife and three children. A new report into the killing was ordered by Prime Minister David Cameron late last year.
Sir Desmond concluded in his approximately 800-page review that members of the Royal Ulster Constabulary knew Finucane was under threat and an officer even proposed the lawyer, who specialised in defending IRA suspects, as a target to UDA assassins.
Sir Desmond also wrote that police and army handlers of agents within the West Belfast UDA "actively furthered and facilitated" his murder, mounting a "relentless attempt to defeat the ends of justice".
Prime Minister David Cameron has said the report contained shocking details, apologised to Mr Finucane's family and accepted that security force collusion took place.
But he stopped short of ordering a full public inquiry which could compel key witnesses formerly of the security forces to give evidence. Mr Finucane's widow Geraldine has branded the latest review a whitewash.
Mr Adams urged the Taoiseach to "initiate an extensive examination of all documents in the Department of the Taoiseach, Foreign Affairs and Justice relating to the north and identify which could assist the family in refuting the British Government's effort to frustrate the Finucane family's demand for a public inquiry".
He added: "A strategic approach is required that would see the government use its diplomatic services across the globe and its influence in the USA, in the EU and at the UN, where the Irish Government now sits on the Human Rights Council, to win support for the Finucane family."
Mr Cameron has ruled a public inquiry out because of the high cost and slow pace of similar inquiries previously. The Labour party's former Northern Ireland Secretary Peter Hain has called for a comprehensive approach to dealing with the past.
Mr de Silva said there was no overarching plan to kill Mr Finucane but noted a "wilful and abject failure" to put a legal framework in place for agent-handling operations. He said there was no evidence government ministers had foreknowledge of the murder plot.
Most of the blame fell instead on the police's disbanded Special Branch, which used one UDA member involved in the killing as an informer and later recruited one of the murderers as an agent. Billy Stobie supplied the guns and Ken Barrett pleaded guilty in 2004 to being part of the murder gang.
An employee of the army's undercover Force Research Unit, Brian Nelson, was positioned as the UDA's director of intelligence responsible for researching targets. Mr de Silva noted that at one stage 85% of the UDA's information on targeting IRA members and supporters came from security sources.
The Finucane case is one of the most-examined of the Northern Ireland conflict, which left more than 3,000 unresolved killings since 1969. While the region's unionists have called for no more focus on the murder, pointing to controversial IRA killings of Protestants, nationalists remain adamantly in favour of fresh investigations.
The UDA murdered more than 250 people, mostly innocent Catholics, before calling a 1994 ceasefire and disarming in 2010. Despite this, loyalist paramilitaries have been accused of orchestrating protests which turned violent in Belfast in recent days in a row over flags, injuring dozens of police officers and threatening elected politicians.
DUP parliamentary leader Nigel Dodds attacked Mr Kenny's remarks on an inquiry, urging Mr Cameron to stand by his stated position that there will be no more costly open-ended inquiries in Northern Ireland.
"Mr Kenny would be well advised to put his own house in order. He leads a Government which only recently attempted to limit the scope and time of the Smithwick Tribunal into Garda collusion with the Provisional IRA.
"Similarly, successive Irish governments have refused to reveal the extent of aid and support they provided to the terrorists of the IRA during the worst years of the Troubles. Mr Kenny is the very last person to be pressing the Prime Minister in any regard."