The Court of Criminal Appeal has reserved judgment on the appeal by John Gilligan against his conviction on drug charges.
The appeal concluded yesterday after a seven-day hearing and Mr Justice McCracken, sitting with Mr Justice Quirke and Mr Justice Peart, said the court would give its decision as soon as possible.
If the court dismisses Gilligan's appeal, it will then fix a date for the hearing of submissions against the severity of his 28-year sentence.
Gilligan was present in court for the entire appeal, which opened on July 1st and was conducted amid heavy security.
Gilligan was jailed by the non-jury Special Criminal Court in March 2001 following a 45-day trial.
He was convicted of possession of cannabis resin and having the drug for sale or supply. He was acquitted of the murder of journalist Veronica Guerin on June 26th, 1996, and also cleared of firearms charges.
Three alleged former accomplices of his - Charles Bowden, Russell Warren and John Dunne - testified against Gilligan.
All three have been freed from prison having completed what Gilligan's lawyers described as "derisory" sentences on various charges and have been placed on the Witness Protection Scheme, under which they received new identities.
In closing submissions yesterday for the DPP, Mr Eamon Leahy SC rejected criticism by Gilligan's lawyers of the Special Criminal Court's refusal to hold an inquiry into the fairness or otherwise of the treatment of Gilligan in custody in Britain. He said the Special Criminal Court had no jurisdiction to embark on any such inquiry.
Replying on behalf of Gilligan, Mr Michael O'Higgins SC, said the prosecution had failed to address many of the issues raised by Gilligan in the appeal.
Counsel said the court had repeatedly asked the prosecution what evidence there was to corroborate the claims of Bowden, Warren and Dunne that Gilligan headed a major drugs gang operating out of Greenmount Industrial Estate in Dublin.
The prosecution had eventually stated there was corroboration through circumstantial evidence, but the matters they had referred to did not constitute corroboration and did not establish that Gilligan was part of a drugs gang, he said.
Mr O'Higgins said the Special Criminal Court judgment was "absoluely ambiguous".
There was no room for ambiguity when a man was serving a very lengthy sentence on the basis of such a judgment, he said.
