Black Widow killer Catherine Nevin has been refused assess to a secret security file into the Dublin Monaghan bombings as part of her bid to secure a miscarriage of justice verdict.
The 55-year-old appeared before the Court of Criminal Appeal where it was claimed the credibility of three prosecution witnesses who sealed her murder conviction were tainted.
Nevin's lawyers are attempting to get access to secret Irish and British documents over claims they allegedly link one of the men to paramilitaries and the 1974 blasts, and would help her appeal bid.
The court heard UK authorities only waived privilege to documents for the Independent Commission of Inquiry into the Dublin Monaghan bombings, gardai and the Director of Public Prosecutions.
Mr Justice Adrian Hardiman, presiding at the three-judge hearing, read one of the papers and refused Nevin's application on grounds it had "no such significance" to advance her case.
Nevin was convicted of murdering her husband Thomas Nevin at their pub, Jack White's Inn in Brittas Bay, on March 19, 1996.
She was also jailed for seven years on each charge of soliciting three different men - William McClean, Gerry Heapes and John Jones - to kill her husband in 1989 and 1990.
An appeal against conviction was dismissed in 2003.
Hugh Hartnett, Senior Counsel, told the court Mr McClean's character was tainted by alleged connections with paramilitary groups, Mr Heapes's reputation soured by his association to Mr McClean and Mr Jones had been the chair of Sinn Fein in Finglas.
He said any evidence about collusion, lying about paramilitary connections, Sinn Fein or the Provisional IRA would have raised questions for the jury.