INDEPENDENT TD Clare Daly has admitted drinking a "house measure" of hot whiskey before she was arrested on suspicion drink-driving.
The Dublin North representative said she took the drink for a cold before midnight on Monday after spending two hours with a family in the south of the city.
"I had no food since lunchtime and did not realise the implications of taking this house measure of hot whiskey," she said.
Ms Daly was pulled over by gardai on the South Circular Road when she made an illegal right turn shortly after leaving the home.
She was unable to give a roadside breath test and was taken to Kilmainham Garda Station where a blood sample was taken.
The tests have been sent to the garda road safety bureau and the results are not expected for around another two weeks.
"I accept full responsibility for what is a serious lack of judgment. I believe that the gardai implementing road safety have a job to do and I support them," she said in a statement on her website.
"Should the test result on the sample provided prove to be above the statutory limit, I will accept the consequences and resolve that this will not happen again."
Ms Daly said she was surprised that details of the incident were leaked without any charges having been brought or confirmation of her being over the limit.
The former Socialist Party member was one of a small number of TDs who late last year exposed allegations that gardai had wiped penalty points from the driving licences of several high-profile people.
AAsked yesterday about her campaign on penalty points, she said: "The point we were making in that situation is that people who violate road safety regulations should be treated in a transparent way and be exposed to the full rigours of the law, not secret deals done behind the scenes.
"And that's something that should absolutely happen in my case if I'm found guilty of any offence, the same it would be for every other citizen.
"I am fully responsible for my actions and I will take whatever consequences are necessary should anything come about," she added.
Last month in the Dail, Ms Daly named a judge as one of those who allegedly benefited from the quashing of penalty points by a garda officer. She made the identification despite being warned by the Ceann Comhairle that it could be defamatory.
It followed the disclosure in this newspaper that at least two judges, a leading rugby player and a television presenter were among those had penalty points written off, according to a garda sergeant, who had compiled a dossier of printouts from the garda PULSE computer, relating to 50,000 cases.
A number of serving and former gardai were also implicated.
Shortly before Christmas, she and three other left-wing TDs backed down on plans to publish the names of thousands of motorists listed in the dossier.
This followed contact with the Office of the Data Protection Commissioner and a warning of legal consequences if they went public with the names. Instead, the deputies called for an independent inquiry into the allegations.