The High Court in Belfast has granted an application to the widow of murdered solicitor Pat Finucane for a judicial review into the British government's failure to make public the Cory Report on controversial killings in Northern Ireland.
In October, retired Canadian Supreme Court judge Peter Cory presented the governments in Dublin and London with reports on six cases - all involving allegations of security force collusion in paramilitary killings on both sides of the border.
The Government published Judge Cory's findings on the two cases within its jurisdiction in December and said it would follow the judge's recommendation and hold an inquiry into whether gardaí helped the IRA kill two RUC men in 1989.
However, London has refused to reveal the contents of the four remaining reports - one of which covers Mr Finucane's death - prompting an exasperated Judge Cory to last week contact the victims' families himself and tell them he was calling for public inquiries in all cases.
"We submit the approach of the British government to the publication of Judge Cory's report is in keeping with the response of the state to the murder of Mr Finucane," Mrs Geraldine Finucane's lawyer, Mr Seamus Treacey, told Belfast High Court: "Delay, obfuscation and a clear reluctance to see the truth revealed."
Mr Finucane's widow is seeking a ruling forcing Britain to publish the report. Lawyer Mr Declan Morgan, for the British government, said Northern Secretary Mr Paul Murphy accepted he had an obligation to publish.
But he argued that because the four British reports were "more complex, more detailed and longer" than those presented to the Irish authorities, more time was needed to weigh up the legal and security implications before they could be published.
Justice Ronald Weatherup ruled the Finucane family had "an arguable case" and set a date for a hearing on March 1st.
Sinn Féin justice spokesman Mr Gerry Kelly welcomed the High Court decision but criticised the British government for "forcing" the families to take use the courts.
"The British Government ... are hiding behind security and legal matters in yet another stalling exercise to prevent the truth about their involvement in a collusion policy from coming out," Mr Kelly said.
Mr Finucane, a high-profile lawyer, was shot dead at his north Belfast home in front of his wife and children by the Ulster Defence Association in 1989.
The case has been dogged by allegations that police and the British army colluded with his killers. Last year an inquiry by London police chief John Stevens concluded the security forces could have prevented his death.