An Irish drunken driver who claimed the inhalation of urine fumes could have skewed his breath-test results has been put off the road for a year.

Robert Bullock (38) claimed that by urinating he broke a mandatory 20-minute observation period prior to providing a breath sample and a new 20-minute period should have begun.

Bullock cited two drink-driving cases from Killorglin District Court in Co Kerry which were thrown out because of the danger the defendants inhaled alcohol from their own urine while in garda custody.

Bullock, of Seabury Grove, Malahide, had pleaded not guilty at Swords District Court to drunken driving at Bissett Strand, Portmarnock.

Garda Mark Gondola said he was conducting a mandatory alcohol checkpoint on September 19 when he stopped Bullock at 12.28am.

The defendant failed the roadside breath test and was taken to Santry Garda Station to be breathalysed.

Garda Gondola said Bullock arrived at the station at 12.55am and was observed by him for 20 minutes before the breath sample was taken.

During this 20-minute period the defendant must not consume anything by mouth.

Garda Gondola said that during the observation period Bullock asked to urinate,.

It was explained to him that he could do so but he would have to be accompanied by the garda. At 1.15am, Bullock was taken to the intoxilyser room where he gave a reading of 40mgs of alcohol per 100mls of breath.

His lawyer stated that garda drink driving guidelines say between 2pc and 5pc of pure alcohol is excreted when a person urinates.

He said Bullock could have inhaled the fumes from his urine, which again could have skewed the result of the breath test. He claimed a new 20-minute period should have begun when his client returned from the toilet, and cited the Kerry cases to support his defence. State solicitor Ann Collins said urinating could only benefit the defendant, as he would have lost pure alcohol by urinating.

Judge Patrick Brady said he was satisfied the 20-minute period was correctly observed.

The judge fined Bullock €500 and put him off the road for one year.