The High Court in Belfast has granted permission for a judicial review into a series of murders linked to a loyalist gang in the 1970s.
The brother of a boy killed by the Glenanne gang, which included members of the RUC and UDR, launched the legal challenge against Northern Ireland's chief constable on Monday.
The gang has been accused of involvement in 120 murders.
Edward Barnard's brother Patrick, 13, was among those killed.
The Ulster Volunteer Force gang was based at a farm in Glenanne, County Armagh.
Patrick Barnard was one of four people who died in a bomb at the Hillcrest Bar in Dungannon, County Tyrone, on 17 March 1976.
His brother sought a judicial review into how the Historical Enquiries Team (Het) - which has now been effectively closed - examined the murder.
Relatives of a number of the other victims of the gang accompanied Mr Barnard to the High Court in Belfast for the hearing.
Counsel for the Crown did not oppose the application and the review is scheduled for May.
Earlier, Mr Barnard's solicitor Kevin Winters said: "The Het has gone and there has been no sight of a wide-ranging review into the Glenanne gang murders, despite the fact that it is known that such a review was almost completed and would have contributed to Edward Barnard's knowledge of the role of state collusion in the activities of the Glenanne gang."
The case is supported by victims' lobby group, the Pat Finucane Centre.