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Law Review: Should stoners be allowed to drive cars?

By Joseph Correy

It is a crime to drive your car with cannabis in your system whether you are high or not. That’s right, smoke a joint on a Saturday and if the pot is in your system on Monday when you drive to work, your licence might be disqualified and you could be fined thousands of dollars.

The Government claims that Mobile Drug Testing conducted by the NSW Police only detects cannabis in the system 12 hours after its use but Defendants charged with driving with an illicit drug in their oral fluid are tending to disagree.

In a judgement last year, Magistrate David Heilpern said he heard hundreds of cases in which drivers said they had waited days, sometimes weeks, after smoking cannabis before driving but tested positive to cannabis anyway.

In the vast majority of cases the time frame has been over 12 hour,” Mr Heilpern said. “Not once has any scientific evidence been produced to this court that supports the contention that the final or any other test only works for 12 hours. It could be that every single one of those defendants are lying to the police. However, on balance, I find that this is unlikely.”

What does the NSW Government say about people who drive sober but have drugs in their system? Roads Minister Duncan Gay told the ABC: “It is illegal to drive with the presence of illegal drugs in your system — it is that simple — if you are caught drink or drug-driving the law is clear“. In other words, stoners should not drive even when it is safe to do so because the fact they are no longer under effect of cannabis is irrelevant.

Despite the words of the Minister, Criminal lawyers are using the law of Honest and reasonable mistake of fact to help their clients beat charges where cannabis has been consumed well before a person gets behind the wheel.

Honest and reasonable mistake of fact is a defence to a charge driving with an illicit drug in your oral fluid where you had an honest belief cannabis was not in your system and the belief was reasonable. This is because if that state of affairs existed, a driver’s act of getting behind the wheel would be an innocent one.

Why might Honest and reasonable mistake of fact be available? The Transport NSW website states that “Illegal drugs can be detected in your saliva by an MDT for a significant time after drug use, even if you feel you are OK to drive. The length of time that illegal drugs can be detected by MDT depends on the amount taken, frequency of use of the drug, and other factors that vary between individuals. Cannabis can typically be detected in saliva by an MDT test stick for up to 12 hours after use”.

The consequence of information such as the above being disseminated by Transport NSW is that a court may accept that if a person drove more than 12 hours following the consumption of cannabis, there belief that the cannabis was out of their system would be honest and reasonable if they relied on material distributed by the Government itself.

The same defence would apply to information on the website relating to stimulants such as methylamphetamine and MDMA.

If you have been charged with Driving with an illicit drug in your oral fluid, contact our criminal law offices in Sydney, Parramatta, Blacktown or Redfern for a free consultation about your prospects of successfully defending the charge.

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Law Review: Should stoners be allowed to drive cars?

Tasmanian Death Match Wrestling – Why aren’t wrestlers charged with assault?

War on Drugs Lost. Should drugs be decriminalized?


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