Kerry North TD Martin Ferris has admitted to drinking two pints and a glass of red wine earlier in the evening before getting into his car to drive about a third of a mile to his home.
The Sinn Féin TD, who was arrested at 1.50am on Sunday on suspicion of drink-driving, said he was fully aware gardaí were on checkpoint duty nearby, but was so confident of not being over the limit that he left the pub in the village of Ardfert and drove towards the checkpoint.
Garda sources said the checkpoint had just been set up when Mr Ferris approached it. He was the only one arrested in the village that night on suspicion of drink-driving. Mr Ferris said he was embarrassed and he would "come out with his hands up" and apologise to the people of Kerry North if he was over the limit.
In a Radio Kerry interview yesterday, Mr Ferris said he had a glass of wine with dinner at 7pm. He went the greyhound track in Tralee where there was a charity night for Adee Football Club and he had three bottles of water.
After 11 pm he had an arrangement to meet Pat Driscoll, manager of the Ardfert football club, in an Ardfert pub. He had two pints with him and they talked outside for up to 20 minutes.
He got into his car, reversed and drove the 50 metres to where the Garda checkpoint was. "I saw the gardaí. I got into my car, I thought I was okay, well under the limit."
The garda stopped him and asked him to blow into the breathalyser. He was "shocked" to have failed the first test, tried again and failed. He was arrested and brought to Tralee Garda station.
"It's the first time that I have ever been breath-tested since I was released from prison the first time, and I was confident myself that I was under the limit." Mr Ferris said he would have to wait two weeks before test results.
"Obviously I am fierce embarrassed and disappointed with my actions . . . I'm hoping it will come back okay and, if not, I will put my hands up."
He had always thought he could have two pints and drive. He "commended" gardaí for doing their duty and this was "totally different" to his arrest (on suspicion of vigilante activity) before the last general election.
Asked if the incident could affect his re-election if he was found to be over the limit, Mr Ferris said: "I stand on my record. Obviously people will be very disappointed in me and that's understandable. I would like people to judge me on my record over the last five years."