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Drink drive offences and post-driving consumption


I had a glass of wine with dinner in a restaurant near to a holiday cottage I had rented. It was the first night and I had dropped off my luggage at the cottage before venturing out in search of a meal. I was staying in quite a remote location and on the way back I got lost in the dark. I had just passed a road I recognised, so I reversed back to turn into it, but one of my wheels went into a ditch and I couldn’t get the car out. A local passing motorist kindly took me back to his house to await roadside recovery.


I knew I wouldn’t be driving again that night, so I accepted a hospitable whisky from my host. Soon after, the roadside recovery people called and took me back to my car so that I could retrieve my wallet from it before they towed it away. As I was doing so, a police car arrived and two police officers questioned me about what happened. When I explained, they smelled alcohol on my breath and asked me to take a roadside breath test, which proved positive. I tried to explain that I had had a whisky after the incident, but they arrested me and took me to the local police station, where I was again breathalysed and was found to be over the limit (57 microgrammes of alcohol in 100 millilitres of breath). I was charged with drink driving. How can I prove that I wasn’t over the limit at the time I was driving?



Leaving aside whether all procedural steps taken by the police were correct, as we do not have any information about this, the issue here is whether your alcohol level was over the limit at the time you were driving, rather than at the time you were breathalysed. The law starts with the presumption that your alcohol level at the time you were driving was not less than that shown in the certificate of analysis of your sample of breath, so it would be for you to prove otherwise.


If convicted, you would be disqualified from driving for a minimum period of 12 months, assuming you have not had a drink drive related conviction in the last 10 years. The magistrates’ courts sentencing guidelines indicate 12 to 16 months for the range 36 to 59 microgrammes of alcohol in 100 millilitres of breath. The court has power to reduce the period of disqualification by up to a quarter of the disqualification period, in return for attending a rehabilitation course at your own expense. If, therefore, the court were to disqualify for 12 months, they would have power (which is entirely within their discretion) to reduce the period to 9 months upon a course examiner’s issue of a certificate of satisfactory completion of the course.


If you wanted to argue that you would not have been over the limit but for having consumed alcohol after driving, the onus is on you to prove this. The court would have to accept both that your account of what you drank and when you drank it is true, and that had you not consumed the whisky after the event, your breathalyser would have been within the limit. This second point has to be proved by way of expert evidence, which can be costly, without any guarantee of success. The expert is independent and has a duty not to assist the court. The prosecution would have their own expert. Bear in mind that back-calculations of alcohol consumed at an earlier time can cut both ways, as the prosecution expert could be asked what your likely alcohol level was at the time you were driving by calculating absorption and elimination rates, etc, based on the alcohol reading when you had the breathalyser test. The courts will not generally get drawn into complex analysis of this sort, so it has to be fairly clear on any evidence supporting you.


As for proving that you did indeed consume alcohol after the event, your good Samaritan should be able to help you by giving evidence on this point. You should also be specific about exactly how much wine you consumed in the restaurant, both as to the size of the glass and the strength of the wine. It is important to obtain evidence to corroborate you, including from anyone who was with you at the time, and your bill for the dinner.


Designed by solicitors, tested by barristers and available around the clock, Road Traffic Representation is an online legal system that allows people accused of a motoring offence to get free advice on how the law will be applied in their case, and referral to a telephone helpline and representation by a barrister in court if required. Practising solicitor Martin Langan spent two years designing the system and creating the data repository which allows the software to analyse road traffic offences with the same authority as a solicitor.

Twitter: martinlangan

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