Court rejects challenge to order allowing convicted drink-driver to exam breathalyser

Seán McCárthaigh

The High Court has rejected a challenge taken by the Director of Public Prosecutions against a Circuit Court ruling which held a defendant in a drink-driving case had a right to a detailed inspection of the breathalyser equipment used to convict him.

Lawyers for the DPP had sought a judicial review of an order made by Judge Catherine Staines in Clonmel Circuit Court in March 2025 and applied for the case to be sent back to the same court for a fresh hearing.

Judge Staines’ ruling had granted Patrick James Flanagan permission to carry out an inspection of the breath testing device known as an “evidenzer” as part of an appeal against his District Court conviction for drink-driving.

The newly published ruling by High Court judge Anthony Barr may have implications for dozens of other cases where motorists are challenging convictions for drink-driving.

Flanagan was arrested on suspicion of drink-driving on May 2, 2022 and subsequently provided two breath samples at Thurles Garda station.

The results produced by the evidenzer showed readings of 66 microgrammes of alcohol – three times the legal limit of 22µg – which resulted in his conviction for drink-driving on July 18, 2023.

Counsel for the DPP claimed Judge Staines had fallen into fundamental error in interpreting a Supreme Court ruling that allowed motorists accused of drink-driving to inspect the relevant breath testing apparatus.

The barrister told the High Court that the judge was wrong in ruling that Mr Flanagan could carry out whatever level of testing deemed necessary by his expert.

The DPP’s lawyers argued she had failed to properly consider the proportionality of the level of inspection sought and that the DPP could not produce the software codes for the evidenzer as they were protected by a non-disclosure clause in the contract between the Medical Bureau of Road Safety (MBRS) and the supplier of the software, Autosober.

In addition, they claimed the Circuit Court had not taken into account the inordinate costs that would follow if a €12,000 machine could not be returned into service after being taken apart, as the MBRS could not stand over its forensic integrity.

The total cost would be over €1 million if all machines across the State were similarly inspected.

Legal representatives of Flanagan said it was clear that Staines was aware she had discretion as to whether she should allow an inspection and to what level after having considered all relevant matters.

The court heard that a consultant engineer, Mark Jordan, had given evidence on behalf of Flanagan to the Circuit Court in which he claimed he needed to access the device’s software codes and algorithms to test its forensic integrity.

Jordan highlighted how software had been manipulated by Volkswagen to give incorrect results about emissions results as well noting issues with Boeing’s engine testing and electronic voting machines in Ireland.

An MBRS analyst, Louise Lawlor, said the MBRS had no difficulty with simulated tests with known quantities of alcohol being conducted under supervision to validate the machine’s accuracy.

Lawlor said the device used with Flanagan, which was subsequently used in different Garda stations, is tested every six months, while checks are also performed by trained supervisors every month.

She gave evidence that Autosober had refused to release its software code on the basis of a non-disclosure clause that protects commercially sensitive information.

However, Barr agreed with the observation by Staines that the MBRS should have negotiated access in its contract if the law entitled Flanagan to inspect the equipment.

Rejecting all grounds raised by the DPP, Barr said it was open to Staines to have concluded what type of inspection was necessary to test the forensic integrity of the evidenzer.

He also noted that Staines had considered the issue of whether the device would be effectively destroyed as a result of an inspection.

The judge ruled there was no basis to alter the findings of the Circuit Court.