A motorist caught with cocaine after he was searched by gardai claimed that he got it from a man in a bar who told him it was a legal high.
Michael Brady (36) failed a roadside breath test and was found to be nearly three times over the legal drink-driving limit.
His partner was in the car with him, and he argued he got behind the wheel because she was even more drunk than he was.
The incident took place at Seatown Road in Swords on November 1 last year.
Sergeant Anthony Collins said he was on mobile patrol when he stopped Brady driving a silver Toyota Corolla shortly after 1am.
Sgt Collins said Brady failed the roadside breath test and he was taken to Balbriggan Garda Station, where he provided a urine sample to gardai.
Sgt Collins said that the sample produced a reading of 223mgs of alcohol per 100mls of urine.
The sergeant said Brady was searched in the garda station and a small package containing a white powder was found.
It was later analysed and discovered to be a single deal of cocaine, with a street value of €20.
The court heard that Brady has one previous conviction for drink driving, but it dated back more than a decade.
Defence lawyer Patrick Jackson said that Brady was previously a self-employed plasterer.
Mr Jackson said the defendant is unemployed and waiting for his social welfare to come through.
The lawyer said that Brady, a father of two, was with his partner when he was stopped by Sgt Collins.
The car belonged to Brady's partner, Mr Jackson said.
The court heard that Brady's partner had also been drinking and she had consumed more than the defendant, who thought it was safer for him to drive.
Mr Jackson also said that Brady did not realise the drug was cocaine, as he got it from a man in a bar who told him it was a legal high.
Judge Dermot Dempsey fined Brady €500 and disqualified him from driving for three years.
The defendant, with an address at Whitestown Drive in Blanchardstown, admitted before Swords District Court to drink driving.
He also admitted to possession of cocaine.