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A recent criminal court case involving a driver acquitted of criminal charges, despite testing positive for the presence of cannabis in his system while driving a car, and despite admitting to smoking cannabis nine days prior to driving, has focused  a spotlight on the current difficulties with criminal offences that relate to drug driving.

For many year it is been a criminal offence  to operate a motor vehicle if affected by alcohol. Drink driving offences target people who attempt to drive a motor vehicle while they have within their system a “prescribed concentration of alcohol.”

To be convicted of a drink drive offence a person must have a “prescribed concentration of alcohol”;  that is a level of alcohol  above a certain prescribed level. If a person drives a motor vehicle with a “prescribed concentration of alcohol” below .05% BAC  and they are not guilty of an offence.

The setting of a prescribed concertation level  recognises that a person can operate a vehicle safely if the level of alcohol within the system is below a recommended level.  The penalties an offender  faces is also dependent upon the blood alcohol reading. The current statutory scheme in New South Wales has three main categories of drink driving offences. Offenders are categorised as  being either  low range, mid range, or high range. The penalties that the court  can impose increases between each range. This penalty regime again  recognises that a person with a higher level of alcohol in their system presents a greater risk to other road users.

In comparison the current “drug driving” offences simply test for the presence of certain drugs within a persons system without testing for the level of the drug.

It is currently an offence to drive a motor vehicle if a person has in their system a “prescribed illicit drug.” A “prescribed illicit drug” means any of the following:

  1. delta-9-tetrahydrocannabinol (also known as THC or cannabis.),
  2. methylamphetamine (also known as speed),
  3. 3,4-methylenedioxymethylamphetamine (also known as ecstasy).

In New South Wales a person who has present in the person’s oral fluid, blood or urine, must not

  1. drive a motor vehicle, or
  2. occupy the driving seat of a motor vehicle and attempt to put the motor vehicle in motion, or
  3. occupy the seat in a motor vehicle next to a learner driver who is driving the vehicle.

As opposed to drink drive offences, which recognises the person may be able to operate a motor vehicle safely with a low level of alcohol within their system, these current laws seemingly do not recognise any safe level of “prescribed illicit drug” within a driver’s system.

The fact that these offences purely seek to detect drugs within a person’s system, as opposed to differentiate between small residue amounts that may have no impact on a person’s ability, has recently come under the spotlight through a recent decision in the Lismore Local Court.

Joseph Carrall, a  33-year-old man,  had already been convicted with driving with an illicit substance in his system.  Speaking with ABC radio program Hack, Carrall said the following:

“Once I was charged and arrested [the first time] I was having discussions with the police officer as to how long after I smoke should it be out of my system and that I should be fine to drive…The officer told me that after a week it should be out of my system and at a safe level to drive.”

A month latter, Carrall was again pulled over by the same police officer in the same spot. He admitted to smoking cannabis nine days before, but based on the advice from the police officer, believed he was able to legally drive. However, he once again tested positive for THC (cannabis)  and was charged.

The charge of “drug driving” was defended in the Local Court.  Hearing the matter, Local Court Magistrate David Heilpern said it had been an “honest and reasonable mistake of fact” and found Carroll  not guilty for his second charge because he had followed the police officer’s advice.

The defence used by Carol may  have limited application for other offenders.  The successful defence,  to a large degree,  was reliant upon the specific advice that Carol had received from the arresting officer. For a person to show that they have an “honest and reasonable mistake of fact”, they would need to demonstrate where that genuine misunderstanding originated.   As such the unique circumstances in this case may limit the actual impact the case has on other similar cases.

The case however does highlight the lack of available information for the general community. The media has focused on the fact that there are a number of conflicting reports in relation to how long certain substances remain in a person’s system, rendering them unable to legally drive.

While it is legal for a person to buy and consume  alcohol if over the age of 18 years, it is an offence to be in possession of a “prescribed illicit drug.” Given that these drugs cannot be consumed  legally,  there  can be an argument to say that any presence  within a person system should preclude  them from driving.  As such, to suggest that there can be any safe level of an illicit  substance in a person system when driving could be considered counterintuitive to the fact that it is illegal to possess those drugs at all.

Notwithstanding that argument,  the current focus on drug driving laws not testing for the  level of drugs in a person system does cast doubt upon the accuracy of some criminal charges.

Depending upon the sensitivity of testing, it has been argued that a person may find themselves being charged with a criminal offence

It is believed a  positive test for a prescribed illicit substance  is possible through inadvertent  or unintentional contact,  such as being around secondary smoke from a person smoking cannabis.   Where the law does not require the police to test for  levels,  it does potentially expose people to criminal prosecution who  have inadvertently been exposed to illict drugs.

With advancements in technology  these fairly recent laws may continue to adapt and change in the future. Until that time there  would continue to appear to be some inconsistencies  in relation to how the current  law deals with these offences which can create a number of complications  for people facing such charges. Given the complexities in this area,  any person facing criminal prosecution should seek proper legal advice.

This article was written by the Kells Criminal Law Team.