Drug Driving Charges and the Defence of Honest and Reasonable Mistake

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Drug driving in NSW

A recent decision in the Local Court of NSW has highlighted the availability of the defence of honest and reasonable mistake of fact against charges of driving with the presence of an illicit substance – or ‘drug driving’.

The case

Nicole Spackman was pulled over for a roadside ‘lick test’ which registered a positive reading. She was then subjected to a secondary test which confirmed the presence of THC – the active in ingredient in cannabis – in her system.

The presence of the substance was confirmed when her saliva sample was sent for laboratory testing, and Ms Spackman was issued with a court attendance notice for drug driving.

She pleaded not guilty to the offence, and it ultimately reached a defended hearing during which she testified that she had not smoked cannabis for weeks but had been taking care of a terminally ill neighbour who had been smoking the plant to alleviate her symptoms.

His Honour Magistrate Heilpern accepted that the defendant’s evidence raised the defence of honest and reasonable mistake, rejecting unbacked submissions by prosecutors that passive smoking could not lead to a positive reading.

The magistrate dismissed the charge accordingly.

The defence of honest and reasonable mistake

The defence is available in ‘strict liability’ cases, which are those for which the prosecution does not need to prove a mental fault element such as negligence, recklessness or intent.

In these cases, the charge must be dismissed if the defendant establishes on the ‘balance of probabilities’ an honest belief on reasonable grounds that he or she was mistaken about a fact that is essential to establishing the offence.

In the context of drug driving, this means a driver must be found not guilty if it is established he or she was not aware of illicit substance being in their system.

The defence is potentially available where the driver can establish that he or she:

  • Had not smoked cannabis for several days,
  • Had been subjected to second-hand smoke only, or
  • Had their meal or drinks spiked.

A requirement is that he or she was not only unaware of the presence of the substance, but that the belief was a reasonable one in all of the circumstances.

Not the first time

This is not the first time Magistrate Heilpern has dismissed a case after accepting a defence of honest and reasonable mistake.

On 23 June 2015, Northern Rivers region resident Joseph Carrall was pulled over by NSW police senior constable Chayne Foster for a random drug test.

The officer asked the driver whether he’d taken any illicit drugs within the last 48 hours, to which Mr Carrall replied, “I had a smoke over a week ago.”

Officer Foster took a sample of saliva, which tested positive for the presence of THC. Mr Carrall was then arrested and taken to the police station to be tested again. He remarked, “I thought I would be alright. It was over a week ago.”

At the station, Carrall’s second test showed traces of cannabis, while a third sample sent to the forensic unit tested positive as well.

Mr Carrall was in familiar territory. A month earlier, on 26 May, officer Foster had pulled him over and recorded a positive test then as well.

The defendant appeared in Lismore Local Court in January 2016 on two counts of drug driving.

He pleaded guilty to the first count but defended the second.

During the hearing, the driver testified that when he was arrested the first time, officer Foster advised him, “If you had waited a week, you would have been fine.”

The defendant added that he relied on this advice before driving again after having smoked cannabis. He gave evidence that the last time he had smoked cannabis was nine days prior to his second arrest.

Mr Carrall admitted that during the period between smoking and being pulled over, he had been at a house where a man had smoked a joint in another room. But he said he genuinely believed the episode of passive smoking would result in the drug being in his system, adding that he convinced he was fine to drive at the time of the second arrest.

Officer Foster testified that it was unlikely he told Mr Carrall to wait a week before driving after smoking marijuana, as this would encourage offending. However, he admitted that he could not remember for certain.

The officer further testified that he believed the MDT devices police use can detect cannabis in a person’s system for up to three to four days after they’ve used it. The officer also said, “Now you could be a smoker and not drive, or a driver and not smoke, and that was the effect of the new laws.”

Magistrate Heilpern found the defendant’s evidence on the witness stand to be “clear and unambiguous evidence”, accepting that he’d been advised to wait for a week, and that he had smoked the cannabis nine days prior to his arrest, and at no later time before being arrested.

His Honour pointed out that it was obvious from the reading speeches made by the ministers who introduced the original legislation into parliament that the law was designed to be used for drugs that were “active” in a person’s system, and would therefore impair their driving.

Prosecuting lawyer Mr Huxtable argued that Mr Carrall’s mistake could not be regarded as reasonable because all drivers should be aware that cannabis could potentially be in their system long after taking the substance.

His Honour disagreed, finding that the combination of the police officer’s previous advice and the evidence that Mr Carrall had smoked nine days earlier, and not thereafter, was sufficient to establish an honest and reasonable mistake.

“the defendant honestly believed that the cannabis was no longer present”, the Magistrate concluded, before finding the defendant not guilty of drug driving.

Going to court for a traffic offence?

If you are going to court for a traffic offence, call or email Sydney Criminal Lawyers anytime to arrange a free first consultation with an experienced, specialist traffic lawyer who will accurately advise you of your options, the best way forward, and fight for the optimal outcome in your specific situation.

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Ugur Nedim

Ugur Nedim

Ugur Nedim is an Accredited Criminal Law Specialist with 25 years of experience as a Criminal Defence Lawyer. He is the Principal of Sydney Criminal Lawyers®.

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