A range of legal sources said the ruling could benefit people serving a reactivated suspended sentence who have lodged an appeal.
The High Court ruled that a legal provision — section 99 of the Criminal Justice Act 2006 — is unconstitutional as it does not provide people affected by it the same right of appeal as everyone else.
This relates to people given a suspended sentence for an offence, which is reactivated when they are convicted of a second offence. However, they can not appeal this second conviction before the suspended sentence is reactivated.
Mr Justice Michael Moriarty said the law was in need of “urgent and comprehensive review”.
The Department of Justice said the “consequences and implications” were “currently being examined” in consultation with the attorney general.
“If someone is in jail on a reactivated suspended sentence and has appealed the other conviction there is a very strong argument that they are unlawfully detained,” said Sean O’Connell, a lecturer on constitutional law at UCC.
“I would say you might see a lot of applications filed before the courts by lawyers in the morning arguing that their clients are unlawfully detained.”
Professor of Law at UL Shane Kilcommins said: “The first consequence is that this applies to the six individuals [involved in the High Court case], but does it apply to everyone else? The answer is no — there is limited retrospective effect.
“It only applies to those whose cases have not reached finality, such as those who have appealed.
“Even in those cases, the question would be asked did the individual raise the legality of the provision at the time or did they acquiesce [such as pleading guilty].”
Leading criminal lawyer Michael O’Higgins SC said that unless a party raised the issue at the time, they would not benefit from the High Court ruling.
He said this was demonstrated in previous cases arising out of laws being deemed unconstitutional going back as far as the ‘A’ case and more recently the ‘Damache’ case.
“If you have been sentenced under the legislation and you haven’t appealed and the time for appeal has elapsed it makes no difference,” said Mr O’Higgins. “If the appeal is pending and you have previously raised the issue you might be able to argue unconstitutionality. But that number would be very small.”
Criminal defence solicitor Dara Robinson said many people in custody for reactivated sentences now had a “solid basis” to apply to have the sentences revoked.