Sinn Féin TD Martin Ferris has been arrested on suspicion of drink-driving.
He was stopped at a random breath test checkpoint shortly after 1am near his home in the village of Ardfert, north Kerry.
The former IRA gun runner was then taken to Tralee Garda Station were he gave a second sample.
A Sinn Féin spokeswoman said the results of that test will not be known for two weeks when a decision will be made on whether he will be prosecuted.
She added that Mr Ferris was confident he was not over the limit.
“Mr Ferris co-operated fully with the gardaí,” the spokeswoman said.
“He does not believe that he was over the limit. He is awaiting the results of the sample taken by gardaí.
“Martin is very mindful of the issue of drink driving, particularly given the high level of fatalities on our roads. He would be the first to be critical of anyone who would drive while over the limit. It is totally unacceptable and indefensible behaviour.”
Mr Ferris was jailed for ten years for his part in an IRA gun running operation.
He was intercepted in September 1984 by the Irish Navy aboard the trawler the Marita Ann off the Kerry coast with seven tons of weaponry in its hold.
The huge arms shipment had been smuggled from America across the Atlantic Ocean in a fishing boat.
Mr Ferris was elected to Kerry County Council and Tralee Council in 1999 and to the dáil for Kerry North in 2002.
As the party’s EU candidate for Munster in 1999 he received almost 30,000 votes.