Minister for Justice Alan Shatter made two attempts to complete a breathalyser test when he was stopped at a Garda checkpoint some four years ago, Taoiseach Enda Kenny revealed today.

The political row about Garda discretion will continue into next week after Fianna Fáil put down a motion of no confidence in Mr Shatter and party leader Micheál Martin queried why the Minister had mentioned he was returning from the Dáil at the time.

Mr Shatter, who made no comment today, was robustly defended by Cabinet colleagues. Mr Kenny stressed his “reforming zeal” and said the Coalition looked forward to defeating the motion on Tuesday and Wednesday.

The Minister confirmed yesterday he failed to complete a breathalyser test “in 2009, or possibly late 2008” because he was asthmatic. “There was no question of my having consumed any alcohol,” he added. Independent TD Mattie McGrath had referred to the incident in the Dáil, but alleged it happened shortly before Mr Shatter was appointed Minister in 2011.

Last week Mr Shatter sparked controversy by disclosing details of a minor “ticking off” of Independent TD Mick Wallace by gardaí for using a mobile phone while driving. He went on to say he had received the information from Garda Commissioner Martin Callinan during a penalty points briefing.

Mr Kenny was asked todat if he had discussed with Mr Shatter whether Oireachtas privilege had been invoked in the Minister’s exchange with a Garda on Pembroke Street in Dublin. The Taoiseach said he had not had the opportunity to speak to Mr Shatter himself about the matter.

However, he said he had been advised that Mr Shatter had made two attempts to complete the mandatory breath test, “but as an asthmatic he was unable to do so”. Mr Shatter had done nothing wrong, he said.

Speaking in Galway, Mr Kenny said he had full confidence in Mr Shatter and the Coalition would “refute strongly” what he described as the “political charge and opportunism by Fianna Fail” in tabling the no confidence motion.

Minister for Justice Michael Noonan described Mr Shatter as a “great Minister” and “the most reforming Minister we’ve had for a long time”. Minister for Health James Reilly said Mr McGrath appeared “confused” about the incident and Mr Shatter had given a clear statement. Minister for Transport Leo Varadkar also defended Mr Shatter. He said those with access to Garda records “need to respect confidentiality”.

Minister for Education Ruairí Quinn said he thought the matter had been dealt with, while the Labour backbencher Kevin Humphreys, who had strongly criticised Mr Shatter for disclosing the information about Mr Wallace, said the Minister enjoyed his full confidence.

“I still believe Mr Shatter was wrong on Prime Time. The manner in which Mattie McGrath has raise this issue through innuendo is equally wrong and I think two wrongs don’t make a right,” Mr Humphreys said.

Mr Martin said further questions had to be asked of Mr Shatter. “I’m curious as to why he saw fit to make a reference that he was on his way home from the Dáil. That normally seems to be invoked as a last resort in certain occasions,” he said.

“That may not be case here but I think he needs to clear that up. I think the only way it can be clarified if there is a Garda report on the incident that it may be made available.”

Earlier, Mr McGrath insisted a report existed but he had not been informed about the incident by gardaí. “People are out there smoking on the streets...members of the public come to me with huge issues of concern and I check out the facts as best I can.”