Brian Meehan, the only person in prison for the murder of journalist Veronica Guerin, can pursue a bid to have his case declared a miscarriage of justice.
The State had attempted to have Meehan's case struck out, but the Court of Criminal Appeal rejected the State's application.
It ruled Meehan's application should go to a full hearing to determine if there had been a miscarriage of justice.
Meehan, 48, from Crumlin in Dublin is serving a life sentence in Portlaoise Prison for Ms Guerin's murder in June 1996.
The Director of Public Prosecutions applied to have his application struck out on the grounds there were no new facts to justify allowing it to proceed and that it was an abuse of process.