The Special Criminal Court has rejected an application by families of the victims of the Omagh bomb for access to State documents.
The application was part of a €21 million compensation claim against those who allegedly carried out the attack.
In a written judgement, the three-judge panel said it did not have jurisdiction to agree to release trial transcripts, books of evidence and statements related to the atrocity.
The civil action is seeking aggravated damages and individual claims from five suspected Real IRA members alleged to have carried out the bombing.
29 people and two unborn babies were killed, and more than 200 people injured, when a bomb exploded in the centre of Omagh on 15 August 1998.
