Director of Public Prosecutions v Kennedy

A technical defect in a roadside breath-test procedure does not automatically invalidate the test. The court must consider whether the defect materially affected the test’s accuracy or reliability. Following the statutory change removing lawful arrest as a condition precedent to admitting station-test evidence, simple proof of an unlawful roadside arrest is insufficient to justify exclusion under Police and Criminal Evidence Act 1984, section 78. Exclusion requires an adverse effect on the fairness of proceedings. Bad faith or oppression may suffice, but they are not exhaustive categories.

The Director of Public Prosecutions appealed by case stated from the decision of justices at Trafford, who dismissed an allegation that the defendant had driven with excess alcohol in his breath. The defendant had made an unsuccessful initial roadside attempt using a Lion Alcometer SL400A, and the mouthpiece was not changed before a later attempt. He subsequently provided positive specimens at the police station.

The justices concluded that the device had been incorrectly assembled, that the arrest was unlawful, and that the station evidence should be excluded under section 78 of the Police and Criminal Evidence Act 1984. The questions concerned the effect of failing to change the mouthpiece and whether the station evidence could properly be excluded.

1. Roadside test. The justices had misread the manufacturer’s instructions. They did not require the mouthpiece to be changed after an unsuccessful first attempt where no sample had been taken for analysis. In any event, the justices should have considered whether reuse by the same suspect immediately afterwards could materially affect the result. It could not. The first question was therefore answered in the negative, although it was badly formulated. [2003] EWHC 2583 (Admin) [16].
2. Station evidence. The validity of the roadside test and the lawfulness of the arrest were not conditions precedent to admitting evidence of specimens properly taken at the police station. The approach in R v Fox (1985) RTR 337 was applied. Parliament had altered the statutory scheme so that motorists could not avoid responsibility merely because of technical defects at the roadside.
3. Section 78 discretion. Simple proof of an unlawful arrest was insufficient, by itself, to justify exclusion of the station evidence. The court had to assess the defect and its effect on the fairness of the proceedings. Bad faith or oppression could justify exclusion, but the possible circumstances were not closed. The guidance in Director of Public Prosecutions v Kay [1999] RTR 109 was applied. Here, there was no more than simple maladministration and unlawful arrest.
4. The second question was answered in the negative. The matter was remitted to the magistrates’ court with a direction to convict. Mr Justice Royce agreed.

• High Court (Administrative Court): Allowed the prosecutor’s appeal by case stated, answered both questions in the negative, and remitted the matter to the magistrates’ court with a direction to convict.
• Trafford justices: On 2 April 2003 dismissed the information after excluding the roadside and station evidence.