Drug driving laws in Australia are strict, and in some ways, surprisingly unforgiving. Most people understand that driving under the influence of drugs is both dangerous and illegal, but many are unaware of how these laws are applied in practice. Whether you’re a medicinal cannabis patient, an occasional recreational user, or just someone interested in staying on the right side of the law, there are some important facts you should know.
Today, we’re looking at five things you probably didn’t realise about drug driving laws in Australia.
1. Not every state tests for the same drugs
One of the most surprising facts is that not all Australian states test for the same substances at roadside testing stops. For example, in Victoria, roadside saliva tests currently only look for three drugs: THC (the active compound in cannabis), methamphetamine, and MDMA.
Despite more and more people using other drugs like cocaine and heroin more often, they’re not included in standard roadside saliva tests in most states. This means that a driver under the influence of these substances might only be caught if involved in a crash that requires them to have a blood test later at a police station or hospital.
2. Medicinal cannabis users aren’t fully protected
A common mistake people make when using medicinal cannabis is thinking they can drive while under the influence. However, you can still lose your licence if THC is detected in a roadside drug test, regardless of whether you have a valid prescription or if you’re impaired at the time. This is because Australian drug driving laws focus on the presence of THC rather than impairment.
Currently, only Tasmania allows a legal defence for unimpaired medicinal cannabis patients. Victoria is set to introduce similar protections in 2025, but until then, it’s important to remember that you’re at risk of charges and disqualifications if you’re caught driving under the influence of prescribed cannabis.
3. Drug driving is an ‘absolute liability’ offence in some states
In New South Wales and some other Australian jurisdictions, drug driving offences operate under what’s called ‘absolute liability’. This means that once a drug is detected in your system, you can be found guilty of the offence, regardless of whether you knew you had consumed it or not.
Even the defence of an ‘honest and reasonable mistake’ - such as accidentally eating a cannabis-infused edible without your knowledge - isn’t available in NSW for drug driving charges.
4. Refusing a roadside drug test can be an offence, too
If you’re pulled over and asked to provide a saliva sample or blood test, you have the right to refuse. However, if you do, it’s important to note that this may also be a refusal offence. The penalties for this can be just as severe as getting a positive result, so in many cases, it’s best to simply take the drug test.
For example, in Western Australia, refusing a test can lead to:
- An immediate 24-hour driving ban
- A fine of up to $500
- License suspension
- Repeat or combined drink and drug driving offences can even lead to jail time
5. Detection windows are longer than you think
Many people mistakenly believe that once they no longer feel under the influence of drugs, they’re safe to drive. Unfortunately, this isn’t how roadside testing works. For example:
- THC, the compound found in cannabis, can be found in saliva for up to 12 - 30 hours after use (and even longer in blood and urine tests)
- Methamphetamine and MDMA can be traceable for up to two days after being used
Learn more about how a drug driving lawyer can help you today
Drug driving laws in Australia are certainly strict, and some people might even say harsh. Understanding the finer points, like which drugs are tested for, the risks for medicinal cannabis patients, and how long substances stay in your system, is incredibly important for keeping yourself and others safe on the road.
If you want to learn more about getting help in these situations, find a lawyer to help with drug driving charges from Donnelly Law Group. With a strong track record of success, they’ll guide you through the legal processes, fight for your rights, and work towards the best possible outcome for your case.
