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Hip flask defence

June 6, 2016 by in category Drink Driving, News with 2 and 1
Home > News > Drink Driving > Hip flask defence
hip flask defences

Our 92% success rate in defending alcohol and drug related charges in 2015 is largely down to legal technical defence strategies that are often unique to the Geoffrey Miller team, having been developed and devised by us. However, there is a factual defence that featured in 4 out of our 107 winning defences last year. That is the “hip flask defence.”

What is this “hip flask” defence all about?

If you consumed alcohol after driving, please forgive us if we talk about “hip-flasks” because this is what a post driving consumption defence is usually referred to in the legal world. We do not seek to suggest that you drank from a hip-flask if you did not. However, this defence historically featured in cases where someone had been involved in a prang and the driver was able to calm their nerves by having a swig of their trusty brandy or other spirit they carried around in a hip-flask!

To be clear, however, this defence extends to alcohol that is consumed post driving regardless of what the alcohol is and where you drank it from!

The law and case law relating to hip flask defence

Courts have grown understandably suspicious of any defence that is reliant on post-driving consumption, largely because it is not considered the norm to drink alcohol after an accident but a sweet cuppa is probably the first thing someone may suggest to calm your nerves. So, be prepared to have raised eyebrows and expect to have evidence to support what you say in court.

In most cases where our client faces prosecution, it is not for the defence to prove anything. The prosecution must prove your guilt beyond reasonable doubt. However, if you plan on raising this particular defence, you have to prove (on the balance of probabilities) that at the time of driving, your alcohol level would have been below the legal limit.

Section 15(2) of the Road Traffic Offenders Act 1988 allows the court to presume that the amount of alcohol measured in an offender’s breath, blood or urine was not less than the amount of alcohol in their system at the time of driving. This statutory presumption will be rebutted if the driver proves that had he not drunk after driving the proportion of alcohol in his breath, blood or urine would not have exceeded the prescribed limit. This statutory defence is set out in more detail at section 15(3) of the Road Traffic Offenders Act 1988.

These issues must be proved by the defence on a balance of probabilities. This means the onus is on the defendant to establish admissible evidence that the alcohol was consumed or absorbed after the relevant time of driving.

In Patterson v Charlton [1985] R.T.R 18 there was an admission made by the defendant that they had driven the car which was used as evidence, but no evidence that they had driven it after drinking alcohol. The case was dismissed but there was a direction made by the Divisional Court that under S.15(3) of the 1988 Offenders Act that rather than the prosecution proving the defendant drank before they drove, the onus of drinking post driving should be on the defendant and up to them to prove.

Evidence we may seek to support your “hip-flask” defence

One of the ways we prepare a defence involving a “hip-flask” defence is by gathering evidence from a suitable forensic toxicology expert to calculate what the expected alcohol level reading would have been at the time of driving based on your instructions of what and when you drank.

The expert will start with the sample you have provided and perform a “back calculation” based on your post incident consumption. They will take into consideration a range of factors to undergo this calculation and these include:

  • The time and date the specimen was obtained
  • Your age
  • Your weight
  • Your height
  • The alcohol that was consumed and the time range over which this was consumed
  • Whether or not you consumed any food before or after driving

Once the above factors have been taken into consideration a report will be prepared to calculate your alcohol level at the time of driving. Reports which support your account of alcohol consumption and the reading you offered to the police are then used as part of the defence.

Pugsley v Hunter [1973] R.T.R 284 established the principle that unless it is obvious that the defendant’s post incident consumption of alcohol explains the excess, it is up to the defendant to call medical or scientific evidence to prove they would not have been above the prescribed limit.

It is therefore, always useful although not essential if we can point to corroborative evidence by way of bar receipts and evidence from witnesses who saw you during the course of the events. In this age of CCTV, this can also prove useful to help build the picture of pre and post driving consumption.

Alcohol Absorption, BAC Calculations and Back Calculations

One of the biological concepts that will be considered by any expert we instruct is the likely period and time of alcohol absorption. When you consume alcohol, it does not immediately hit your blood stream but takes time to travel from your mouth to your stomach. It is only once it diffuses through to your small intestine that this alcohol can be counted towards a reliable BAC (Blood Alcohol Concentrate) Calculation, not to be confused with a back calculation.

Back calculations are also often undertaken by the police when you have provided a breath, blood or urine sample that was under the limit but the police suspect that you would have been over the limit at the time of driving. They therefore undertake a similar process to that describe above to prove that you would have been over the limit. This is usually only undertaken by the police in cases where a serious injury or fatality has arisen.

What if you drank shortly before driving?

If you drank within 1-2 hours before driving, it is possible that the alcohol you consumed was not absorbed into your blood stream at the time of driving, especially if you also consumed food when drinking alcohol as food slows down the absorption process. If this was the case, there could be a valid argument that you were not over the drink drive limit at the time of driving even if you were over the limit at the time of providing a sample of breath, blood or urine to the police.

This would not be a post driving consumption defence but we would follow a similar exercise in terms of obtaining toxicology evidence to support the argument that you would not have been over the drink drive limit at the time of driving.

What offence will I be charged with?

Even if the police have arrested you at home, if you have been seen/suspected of driving the police can ask you to provide a breath specimen.

If you blow into the breathalyser machine or provide blood or urine and your result is positive, you will be charged with drink driving.

If you fail to blow into the breathalyser machine or refuse to provide blood or urine if required to do so, you could face the charge of failing to provide a specimen. A “hip-flask” defence would then become irrelevant as there is no need to prove that you were over or under the limit at the time of driving. All the prosecution will be considering if you fail or refuse the drink drive test is whether you did so without reasonable excuse.

What sentences do these offences carry?

Many people are unaware of the implications of being convicted of drink driving or failure to provide a specimen.

If you are found guilty of drink driving:

  • You will receive a minimum disqualification of 12 months from driving
  • If you have a previous alcohol related driving conviction within 10 years of this offence the minimum period of disqualification will be 36 months
  • You could face the prospect of losing your job
  • You will have a criminal conviction that will remain on your licence indefinitely and will be visible on all CRB checks. It will also appear on your driving record for 11 years
  • Visa restrictions particularly in Australia and the USA
  • The possibility of undergoing medical examinations before you can drive again

If you are found guilty of failing to provide a specimen:

  • The penalties for fail to provide depend on how the police describe the failure and how they describe your demeanour
  • You could face the prospect of losing your job
  • You will be disqualified for a minimum of 12 months
  • If you have a previous alcohol related driving conviction within 10 years of this offence the minimum period of disqualification will be 36 months
  • A criminal record with the conviction for failure to provide a specimen remaining on your driving licence for 11 years. If you are a professional, for example a doctor/solicitor/accountant, you will most likely have to report the conviction to your regulatory body
  • Visa restrictions particularly in Australia and the USA

Scared of going to court?

We mentioned above our high levels of success in defending drink related charges. However, if the thought of going to court and being quizzed under oath terrifies you, please bear in mind the fact that most of our cases, even our “hip-flask” defence cases are won without a client’s evidence being heard.

Of the 107 cases that were successfully defended last year most (86%) were won before our client had to give evidence or any defence expert’s evidence was presented. This is because we are usually successful in persuading the prosecution to withdraw all charges on the day of trial if not before. If the prosecution are insistent on continuing with the case, the court usually agrees the matter should be dismissed by the time we finish (tear apart) with the prosecution case.

This means that it is extremely likely that with the help of the Geoffrey Miller team we will achieve your acquittal and this will be done without you having to utter a word (aside from the phrase “Not Guilty!”)

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  • G McKeeman
    on September 7, 2018 Reply

    Can you please explain how I get a back calculation and how much it costs?



    • Jeanette Miller
      on September 11, 2018 Reply

      A back calculation can be conducted by a forensic toxicologist. However, it is best to involve solicitors to instruct this kind of expert. The cost of a report can vary but will generally be between £3-500.

      Please contact us if you wish for us to assist with this.

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