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Defending a Drug Driving case?

Written by: Alan Baker 9th May, 2017

Driving under the influence of drugs, either illicit or prescription, has been an offence for many years but before March 2015, the Crown had to establish that the individual was impaired to drive.

Historically about 40% of proceedings in Magistrates Courts for drug driving were withdrawn or dismissed. The comparable figure for drink driving was 3%.

However, given that one in ten 17-24 year olds have taken drugs before driving and nearly 25% of fatal road accidents showed drugs were a key factor, the Government decided to impose statutory limits for certain substances and consequently the police no longer need to prove impairment for this new offence.
The change in law works alongside the old legislation but makes it an offence to drive while over a specified limit for each of the 16 drugs listed. This makes the offence similar to that for driving with excess alcohol, given that statutory limits now exist.

From a scientific perspective, the cases undertaken by Bericon Forensics show an emerging pattern, one very similar to the types of cases which we have undertaken in drink driving for the last 30 years.

More specifically, we have prepared reports in the following cases, all of which show comparability to drink drive prosecutions:

Case Study 1:

“In Charge” prosecutions: similar to drink drive cases where the individual wouldn’t have driven until under the legal limit.

The defendant was in the driver’s seat of the vehicle and officers noted the smell of cannabis emanating from within the car.

He gave a positive roadside test for the presence of cannabis and a sample of the defendant’s blood was taken for analysis.

This sample was subsequently shown to contain tetrahydrocannabinol (THC) at a concentration of 3 microgrammes per litre (3.2ug/l). This THC concentration is above the statutory limit of 2ug/l but given that defendant was not seen to be driving the vehicle he was charged with being in charge of a vehicle.

Bericon was requested to prepare a report that assessed the significance of THC being found in defendant’s blood and, most significantly, if his reading would have fallen below the statutory limit when he intended to drive.

Our report suggested that it was most probable that his reading would have been below 2ug/l when he would have returned to drive his vehicle and the defendant was acquitted.

Case Study 2:
Post-incident or post-driving consumption of drugs: similar to cases where individual has consumed alcohol after having driven.

The defendant was spoken to by police officers and took a roadside drug test which indicated the presence of cannabis. He was arrested and taken to the police station.

A blood sample was taken from him and subsequent analysis of which showed there to be THC present at a concentration of not less than 3.3ug/l, which exceeds the statutory limit of 2ug/l.

We were instructed that the defendant consumed about one gramme of cannabis immediately after he was stopped and prior to him speaking to police officers.

Bericon was requested to prepare a report that assessed whether the cannabis compounds could be present as a consequence of the defendant’s consumption of cannabis in the manner suggested.

Our findings were on the assumption that the defendant consumed the amount of cannabis at the time suggested that this could have given rise to the reported blood THC reading or at least have significantly contributed to it to a level that without it, his reading would have been below the statutory limit. The defendant was acquitted.

Case Study 3:
Unknowing consumption of drugs: similar to cases where the individual has consumed alcohol unknowingly

Police officers spoke to the driver of a motor vehicle and requested he took a roadside drug test. The test indicated the presence of cannabis and the

defendant was arrested and taken to the police station.

A blood sample was taken from him and subsequent analysis of which showed there to be THC present at a concentration of not less than 7ug/, which exceeds the statutory limit of 2ug/l.

We were instructed that the defendant consumed a cake which reportedly contained a quantity of cannabis. He reported that the whole cake consumed 6.5 grammes of cannabis and which was divided into six portions, three of which were consumed by him.

Bericon was requested to prepare a report that assessed whether the cannabis compound could be present as a consequence of the defendant’s unwitting consumption of it in the cake.

Our findings were that on the assumption that the cake contained the quantity of cannabis that was suggested and that the defendant consumed it in the amounts and at the times suggested that this could have given rise to the reported blood THC reading or at least have significantly contributed to it and therefore without this consumption his reading could have been below the limit. The defendant was acquitted.

All the above cases have been undertaken by Bericon Forensics in the last 12 months and show that in some situations, consideration should be given to a whole range of factors about drug use and drug driving prosecutions.

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