Former politician Ivor Callely is out of prison on bail pending his High Court action aimed at getting temporary release.
High Court President Mr Justice Nicholas Kearns said the balance of justice favoured admitting the former Fianna Fail politician to bail, pending the outcome of his judicial review.
Callely is taking legal action against the Minister for Justice and the Governor of Wheatfield Prison over a refusal to grant him either temporary release or enhanced remission.
Callely (56) was jailed last July after admitting he fraudulently claimed €4,207.45 in expenses from the Oireachtas on forged mobile phone invoices. He was sentenced to a total of five months in prison.
The judge accepted arguments from Callely's lawyers that his judicial review would become pointless if he was not granted bail.
The judge also agreed with Callely's lawyers he had been a model prisoner, did not represent a flight risk, and was not at risk of re-offending.
At 3pm Callely was brought from a building within the court complex to a waiting prison van.
Wearing a dark blue suit, a light blue shirt, and a green-and-blue striped tie, he looked fit and healthy.
Clutching documents in his left hand, his right hand was chained to that of a prison officer. He declined to comment as he was put into the back of the van and driven away.
The former junior minister briefly returned to prison to have his bail application processed. Callely arrived at Wheatfield Prison at around 3.30pm. He was then picked up by a man and woman in a red Toyota Corolla.
Earlier, Mr Justice Kearns said the case had raised some "important legal issues," particularly concerning a prisoner's entitlement to enhanced remission of up to one third of their sentences for good behaviour.
Given the importance of these matters, the judge said the action should be heard as soon as possible, and would be given priority by the court.
Callely was granted bail on his own bond of €100, which was to be entered into before the prison governor.
Kieran Kelly BL, for Callely, said as his client is entitled to a third remission he would already be out of prison.
If the normal one quarter remission is applied, his release date is November 18 next.
If he was denied bail, and should he win his case, counsel said his client would "not be able to get back those extra days spent in prison".
If bail was granted, and his judicial review action was unsuccessful, counsel said, his client would return to prison to serve out the remaining days of his sentence.