The Supreme Court ruled that a section 17 breath-test certificate was not admissible in the circumstances of a drink-driving case involving three attempts to provide breath specimens. It answered both questions referred in a consultative case stated in the negative.
The case was referred by a Dublin Circuit Court judge after the accused challenged the prosecution’s reliance on a certificate produced during testing at Dún Laoghaire Garda station. The referral asked whether Gardaí could require two breath specimens despite an earlier incomplete test, and whether the certificate was admissible.
The judgment records that the accused was arrested in February 2002 after a Garda formed the opinion that he was incapable of properly controlling a vehicle because of alcohol. At the station, the Garda made one requirement under section 13(1)(a) of the Road Traffic Act 1994 for two breath specimens.
The first attempt produced no recorded specimen. On the second, the machine recorded one specimen at 88 micrograms of alcohol per 100 millilitres of breath, but marked the test incomplete. A third attempt produced two specimens, recorded at 88 and 87 micrograms. The machine calculated a final reading of 71 micrograms, and a section 17 certificate was issued from that test. The prosecution accepted that the third attempt was the only completed test and the result it relied on.
The accused’s counsel argued that the law allowed a requirement for only two specimens and that the third attempt exceeded that power. The prosecution submitted that there had been one requirement, with further attempts to complete it.
Delivering the judgment on 16 October 2008, Denham J said there had been a single requirement, followed by three attempts. The Court’s reasoning focused on the machine’s use of two specimens from the same attempt to produce a certificate, with a 17.5% deduction applied to the lower reading. That process could leave out a lower specimen recorded in an earlier, incomplete attempt and could produce a certificate where the earlier reading might not support prosecution.
The Court concluded that a system which could disregard a lower earlier specimen in favour of later, higher readings was unfair and did not meet the requirement of due process. It held that, in this case, where the second attempt recorded one specimen and was incomplete, the third attempt could not provide the basis for the section 17 certificate. The judgment answered the questions referred; it did not determine a broader factual question about the accused’s guilt.