Barry Cowen claimed €7,166.25 in travel allowance after being caught drink-driving in 2016, according to Oireachtas records.
Mr Cowen, now the Minister for Agriculture, was found to be over the limit, received a €200 fine and was disqualified from driving for three months after being stopped at a garda checkpoint on his way home to Offaly after he attended the All-Ireland Football final in Dublin on September 18th.
From September 29 to December 22, 2016, Mr Cowen claimed the full travel expenses available each month, amounting to €7,166.25.
In 2017, Mr Cowen continued to claim the same amount of travel allowance every month.
The Laois-Offaly TD has since apologised to Taoiseach Micheál Martin, who only learned of the ban on Friday, and labelled the incident as a "serious lapse of judgment".
From March 30 to December 22 in 2016, Mr Cowen claimed the full amount of travel and accommodation allowance (TAA) available, of €2388.75 per month, amounting to €24,216.98, including an additional sum of €329.48 which was also claimed.
The amount Mr Cowen claimed did not change after the incident, and continued to claim the full amount available.
TAA covers the costs associated with travel to and from Leinster House, overnights and, for TDs only, other travel expenses including constituency travel.
Today, an adult monthly ticket from Clara, Co. Offaly, Mr Cowen's constituency, and Dublin Heuston costs €392
The Laois-Offaly TD told RTÉ's The Week In Politics that he had been driving on a provisional licence at the time, despite being a TD since 2011. He said that he had since "regularised" this and obtained his full licence.
He admitted that he had driven without a fully licensed driver at times, but was not unaccompanied at the time of the offence. Mr Cowen said that he had never had a full licence previously.
Mr Cowen has committed to addressing the controversy in a Dáil statement amid further concern over why he did not have a full driving licence by the age of 49, who served as a county councillor from 1991 and TD since 2011.
Minister for Justice Helen McEntee said she accepted Mr Cowen's apology.
“I do not agree with what happened, he has apologised, I accept that and I think it is important that the law was applied to him at the time," she said.
“I think he has said he would be willing to make a statement in the Dail in terms of questions and that would be appropriate.”
The Irish Road Victims Association (IRVA) has called for the Agriculture Minister to step down from his role.
However, the Taoiseach believes Minister Cowen should not be punished for something that happened years ago.
Speaking to Red FM, Micheál Martin said: "Are you going to condemn someone for the rest of their life for something that might have happened four or five years ago?
"I think there is an issue of proportionality in that regard."
The Department of Agriculture and Mr Cowen have been approached for comment.