A GARDA Detective Inspector who had a whiskey to "steady his nerves" after knocking down a young girl outside his Dublin home has been cleared of trying to frustrate a drink driving prosecution.

Det Insp Paul O'Brien admitted drinking a measure and a half, insisting he did so because he was "shook up" following the accident in which he backed his patrol car over a four-year-old girl on a scooter.

The girl became trapped under his rear wheel but was unhurt apart from bruising.

The case against him was dismissed after Dublin District Court heard the investigating garda initially saw no sign that Mr O'Brien had been drinking, only later noticing he was flushed and glassy-eyed.

The defence argued that because Mr O'Brien was not under suspicion of drink driving when the garda first spoke to him, he could not be guilty of trying to frustrate a prosecution by then having a drink.

Judge Bryan Smyth ruled that the accused had no case to answer.

Mr O'Brien, with an address at Moyville, Rathfarhnam, had denied consuming alcohol with the intention of frustrating a drink driving prosecution on May 6, 2013.

The court heard he had ultimately tested just over the alcohol limit but was never charged.

The girl's parents, Tracy and David Kirwan said in evidence they were visiting Mr Kirwan's father William, who lived nearby, and preparing a picnic for a trip to the zoo.

They were outside at around 10.30am as their daughter was playing on her "flicker" scooter on the footpath. They heard a bang and saw her trapped under her scooter, which was under the rear left wheel of Mr O'Brien's Ford Mondeo. They ran to her and Mr Kirwan lifted the car to relieve the pressure while the accused moved forward to help free the girl.

"I said did you not check your effing mirror, he said he did", Mr Kirwan told the court.

He and his wife brought the girl to Tallaght Hospital.

William Kirwan then went to the accused's house and his car was gone. Mr O'Brien's wife said she would call him. Mr Kirwan returned home to phone the gardai. Mr O'Brien came to his door within 10 minutes, explaining that it had been an accident.

Garda Donal Ashe told the court he went to the scene, spoke to William Kirwan, then went to Mr O'Brien's home. The accused told the garda he had not seen the girl before the accident happened.

After the parents came to get the child and left, the accused thought "that was it and left".

Garda Ashe told him it may be treated as an official accident and left to speak to a superior officer.

He returned and made a requirement of Mr O'Brien to provide a breath sample.

"At this point he informed me that he had taken a drink to calm his nerves as he was shook up by the incident", Garda Ashe said.

He did not carry out the breathalyser test then and waited for Supt Peter Duff and Insp Derek Maguire to arrive. The accused was tested and failed.

Mr O'Brien told Insp Maguire he had taken a drink when he got back to the house and it was a measure and a half of Bushmills. He was arrested and taken to Terenure Garda Station, where he provided a sample which had a reading of 29mcg of alcohol per 100ml of breath. This was over the 22mcg limit but the accused was never prosecuted for drink driving.

Gda Ashe said when he spoke to Mr O'Brien in his house first, he was "calm and coherent", but when he returned Mr O'Brien's face was "flushed red and his eyes seemed glassed over".

In cross-examination, Defence Barrister Martin Dully BL put it to the garda that before he disclosed that he had taken alcohol, Mr O'Brien had appeared "absolutely sober".

The garda replied that he did not form any opinion at that time, and when he returned, he noticed a change in the defendant's appearance.

Supt Duff contacted the Garda Siochana Ombudsman's Commission, which informed him that it would be leaving the investigation to the gardai.

He told Mr O'Brien of this and noticed the accused had bloodshot eyes, slurred speech and smelled of alcohol.

"If the prosecution's evidence is that Mr O'Brien appears to be stone cold sober following the accident... how can it be said that Mr O'Brien's subsequent consumption of alcohol had as its intention the frustration of a (drink driving) prosecution?" Mr Dully asked."It's just conceptually impossible".

The State Solicitor argued that the defendant had a case to answer, saying he had been "no ordinary suspect" and had taken whiskey knowing full well he was likely to be breathalysed.

Judge Smyth ruled that the State had not made out a case against the accused and dismissed the charge.

By Andrew Phelan

Online Editors