The Director of Public Prosecutions v Vince & Ors

A failed breath-analysis attempt does not, by itself, require the police to abandon the procedure and obtain blood or urine. A further breath test may be conducted where the device is available, practicable to use, and known to be operating reliably. Administrative forms used to guide drink-driving procedures do not have statutory force, and omissions in them do not invalidate otherwise lawful evidence. The tribunal of fact must nevertheless assess whether the device was reliable and the result accurate. A roadside breath reading is admissible as evidence supporting the reliability of a later station test, although it cannot itself establish the offence. On a submission of no case, the court must distinguish legal insufficiency from evidential unreliability and must give adequate reasons for its conclusion.

Two appeals by way of case stated concerned breath-analysis evidence following an Ambient Fail message on a Lion Intoxilyzer 6000UK.

In Kang, the District Judge convicted the defendant under section 5(1)(b) of the Road Traffic Act 1988. The officer restarted the machine, obtained two further specimens, and relied on the lower reading. The issues were whether the restarted procedure was lawful, whether failures to complete parts of form MG DD/A affected admissibility, and whether the roadside reading could support reliability.

In Vince, the magistrates dismissed the case at the close of the prosecution evidence. The prosecution appealed, arguing that the evidence was sufficient to call for an answer. The central issues were whether procedural defects invalidated the station reading, whether the evidence was too unreliable to support a conviction, and whether the statutory warning had been given.

1. Both appeals dismissed. The Administrative Court answered the Kang questions affirmatively in substance and upheld the dismissal in Vince.

2. Under section 7 of the Road Traffic Act 1988, the officer was entitled to require further breath specimens after the first attempt failed. Section 11(3) permitted the first attempt to be treated as no specimen having been provided because the defendant’s manner of blowing prevented the test from being properly carried out. The availability of a reliable and practicable breath device meant that the statutory conditions for requiring blood or urine at the police station were not established.

3. Form MG DD/A was only a practical guide. Its indication that blood or urine would usually be sought after an Ambient Fail was not mandatory. The form had no statutory force. The omissions in paragraphs A18 and A19 did not invalidate the later results, particularly since the original printout supplied an accurate record of the failed attempt.

4. The fact-finder had to determine whether the machine was operating reliably and whether the result was accurate. The roadside reading could be considered as one item of evidence supporting that assessment. It was not treated as the basis of conviction; the offence was established, if at all, by the station test under section 7. The same conclusion would have been open even without the roadside reading because other evidence supported reliability.

5. In Vince, the case stated was inadequately drafted. It failed to identify the alleged inconsistencies between the officers’ evidence and did not explain the procedural defect said to breach section 7. Evaluation of contradictory evidence is ordinarily a matter for the fact-finder, not a question of law on a case stated. The magistrates might nevertheless have been entitled to dismiss the case if the evidence was so unreliable that a safe conviction was impossible, or if the statutory warning under section 7(7) had not been given. Their reasons were unsatisfactory, but the stated case did not demonstrate an error of law.

6. The court stressed that parties must scrutinise a draft case stated and seek amendment where necessary. The Administrative Court is confined to the facts stated. Amendment could have been sought under section 28A of the Senior Courts Act 1981, but the circumstances did not justify remitting the case for redrafting or ordering a new hearing.

• Magistrates’ courts: Kang was convicted after trial. Vince’s case was dismissed on a submission of no case to answer.
• High Court (Administrative Court): Both appeals by way of case stated were dismissed.