The Court of Criminal Appeal will deliver its decision tomorrow on the appeal of Colm Murphy against his conviction arising out of his role in the 1998 Omagh bombing.
Murphy (51) of Jordan's Corner, Ravensdale, Dundalk, a building contractor and publican, remains the only person convicted in connection with the bombing in August 1998.
A total of 29 people, including a woman pregnant with twins, were killed.
Murphy was convicted by the non-jury Special Criminal Court in January 2002 on a charge of conspiracy to cause an explosion.
During the hearing of his appeal against conviction and sentence last month, Murphy's counsel, Mr Michael O'Higgins said that "a huge element" of the appeal was based on a claim that two Garda officers had falsified interview notes and had committed "massive perjury".
In all, there were 45 grounds of appeal.
It was also argued the Special Criminal Court had wrongly admitted evidence of interview notes and alleged utterances of Murphy; that the trial was unsatisfactory because of an almost two-month break in proceedings and that telephone records had wrongly been admitted in evidence.