The father of an IRA member shot dead by the SAS close to Loughgall in Co Armagh in 1990 has won a five-year legal battle over the disclosure of confidential intelligence reports.
The PSNI must now hand over unabridged information about the shooting of Martin McCaughey and Dessie Grew to the coroner, who will hear the inquest into their deaths.
The judgment overturned an earlier Northern Ireland Court of Appeal ruling that the PSNI was legally entitled to limit the information passed to the coroner.
Mr McCaughey, a 23-year-old former Sinn Féin councillor, and Mr Grew, aged 37, were shot dead by the SAS and the nature of their wounds raised fresh allegations about a so-called 'shoot-to-kill' policy being operated by British security forces.
The inquest into the deaths has long been delayed and Mr McCaughey's father Owen launched his lengthy legal bid after the PSNI Chief Constable refused to release the intelligence.
Following a six-day hearing in January, the Law Lords in London today gave their ruling that the reports must be disclosed in full.
Later in the judgment, the five Law Lords upheld a Court of Appeal ruling that coroners' courts in Northern Ireland should not be permitted to reach verdicts of 'lawful' or 'unlawful killing' about the killing of another IRA man in a separate incident.
However they said the jury which hears the inquest into the death of Pearse Jordan may make 'relevant factual findings' pertinent to the killing.
Mr Jordan, 23, was shot dead by the RUC in disputed circumstances in the Falls Road area of west Belfast in November 1992.
The solicitor acting for both the McCaughey and Jordan families welcomed the decisions which they said would have serious implications for the inquests.
Peter Madden said 'the RUC, now the PSNI, can no longer dictate which information it chooses to withhold from scrutiny'.
Sinn Féin MLA Francie Molloy welcomed the judgment and said it paved the way for 'full and open inquests' into the killings of Mr McCaughey and Mr Grew.