Post Driving Drug Consumption

In the run up to the 5 year anniversary of the drug driving laws in the UK in March 2020, we address a number of novel issues relating to drug driving.

A commonly known defence to the charge of drink driving is the “post driving consumption” defence. This defence, usually referred to as an “Hip-Flask” defence in the legal world generally revolves around cases where the suspect has been in an accident, or just returned home and decided to have a swig of their favourite alcohol of choice to calm their nerves. It is this consumption of alcohol that post dates the alleged driving of the offender that could form the basis of the defence. In essence, were it not for the post driving alcohol, the suspect would not have been over the drink driving limit.

However, this defence does not only relate to alcohol, but also relates to drug consumption. Since the introduction of the offence of driving with excess drugs in March 2015, there has been a set amount of illegal and medicinal drugs that drivers are permitted to have in their blood whilst driving. As the Prosecution in any case have to prove that the amount of drug in the driver’s system was in excess of this specified drug limit, the “Hip-Flask” defence, which is not aptly named for drug driving, is incredibly relevant.

Section 15(2)(b) of the Road Traffic Offenders Act 1988 allows the court to presume that the amount of drug measured in an offenders blood or urine was not less than the amount of drug in their system at the time of driving. This however can be rebutted if the driver can prove that had he not consumed sufficient drug prior to the blood or urine test, that the amount of drug in their system would not have exceeded the specified drug concentration limit.

This defence is further set out in 3(a) of the Road Traffic Offenders Act 1988 states:

The assumption in subsection (2)(b) above is not to be made if the accused proves—

(a) that he took the drug before he provided the specimen or had the specimen taken from him and—

(i) in relation to an offence under section 3A, after the time of the alleged offence, and

(ii) otherwise, after he had ceased to drive, attempt to drive or be in charge of a vehicle on a road or other public place, and

(b) that had he not done so the proportion of the drug in his blood or urine—

(i) in the case of a specified controlled drug, would not have exceeded the specified limit for that drug, and

(ii) if it is alleged that he was unfit to drive through drugs, would not have been such as to impair his ability to drive properly.

Therefore, if you consumed for example, cannabis, edibles, or any other drug following driving, you could potentially have a “Hip-Flask” defence.

However, the law has grown quite sceptical of any defence which relies on the “Hip-Flask” defence, and therefore, it is incumbent on the defence to prove on a balance of probabilities or in other words that it was more likely than not, that if not for the drug you consumed, you would not have been over the specified drug concentration limit.

We frequently involve forensic experts to consider issues in our drug driving cases and have asked for their views about the ingestion of cannabis after driving. Something many drivers have done in a panic when stopped by police:

Therefore, whilst there does not appear to be a great deal of published data or case law surrounding the subject, it is certainly possible that if you have consumed drugs post driving, that the post driving consumption defence may be relevant to your case.