The British Government is facing mass legal action over alleged collusion with loyalists in murders in Northern Ireland in the 1970s.
A total of 32 families are to claim the police, army and Northern Ireland Office facilitated or sanctioned the cooperation, their solicitor said.
High Court writs have been served in relation to a test civil case involving three deaths.
Lawyer Kevin Winters said: "The failure of the PSNI to sanction an overarching, thematic Historical Enquiries Team (HET) report linking all of the atrocities together and the recent collapse of the Haass proposals on the past has left many families with little alternative but to take legal action to get justice and closure."
The court action focuses on killings linked to a loyalist group in Mid-Ulster known as the Glenanne gang, who legal representatives of the family claimed were linked directly and indirectly with the security forces.
They were associated with the killing of up to 120 people in a murder spree spanning a five-year period of the late 1970s in Mid Ulster.
Among their victims was nationalist SDLP branch secretary Denis Mullen, who died on 1 September 1975.
The weapon used to gun him down at the front door of his family home in Collegeland, Co Armagh, had been stolen from Glenanne Ulster Defence Regiment (UDR) base four years earlier, Foyle MP Mark Durkan has told the House of Commons.
The UDR was a branch of the army recruited within Northern Ireland that has been at the centre of repeated criticism by nationalists for its role during the conflict.
Late last year, Mr Durkan told MPs Mr Mullen was shot 27 times at close range.
He said: "His wife Olive ran for her life through the house with bullets slamming into the walls behind her and crawled across the kitchen floor before climbing out through a window to run for help.
"Their daughter, Denise, aged four, heard the shots and got out of bed to find her father bleeding and dead at the front door.
"She stood over his body for an hour, her nightdress soaked in blood, before the police considered it safe enough to remove her and her 11-month-old brother, who was still in his cot."
A test civil case is being taken by Denise Fox, Mr Mullen's daughter.
Writs have also been served relating to the killings of Patrick Falls, a Catholic murdered during a 1974 attack on a bar in Clonoe in Co Tyrone, and the death of Betty McDonald at a bar in Keady, Co Armagh.
Mr Winters said the first preliminary hearing of an inquest into Ms McDonald's death would be held after Easter when his firm would ask the coroner to consider all Glenanne cases on a linked basis.
He added: "We are supported in this approach by the Police Ombudsman Dr Michael Maguire whose investigation into allegations of misconduct and criminality is already under way.
"To that end the pending litigation not only supports the call for a choreographed legal oversight but will also bring long overdue compensation for the horrendous losses suffered by all families."
Former US diplomat Dr Richard Haass chaired five-party Northern Ireland talks aimed at devising a structure to address past atrocities.
The discussions ended without agreement before the New Year.