Who Legally Needs An Alcohol Interlock In Australia?
If you’ve been charged with a drink driving offence in Australia, you might be wondering whether an alcohol interlock device is something you’ll legally need to install. These devices aren’t just optional add-ons—they’re a mandatory requirement for many drivers who have committed serious or repeat drink driving offences.
With that being said, we’ll break down exactly who is legally required to use an alcohol interlock in Australia, how the scheme works in different states, and what it means if you’ve been ordered to participate. Whether you’re facing a court order or just want to understand the legal thresholds, here’s what you need to know.
What Is An Interlock Device?
An interlock device is a breath-testing system that’s electronically connected to a vehicle’s ignition. Before the engine can be started, the driver must provide a breath sample through the device. If any alcohol is detected above a very low limit (typically 0.02% BAC or even zero, depending on state regulations), the vehicle won’t start. This technology is designed to physically prevent someone from driving under the influence of alcohol, offering a practical solution to help reduce repeat drink driving offences.
The device doesn’t just stop the car from starting—it also requires random retests during longer trips to ensure ongoing sobriety behind the wheel. All results are recorded and may be reviewed by authorities, especially if the interlock is court-ordered or part of a licensing program.
Interlock devices are most commonly used as part of legal or administrative penalties for drivers convicted of high-range or repeat drink driving. However, in some cases, they may also be voluntarily installed as part of workplace policies or personal accountability measures. Ultimately, interlock devices serve a clear purpose: to make roads safer by ensuring that individuals with a history of drink driving are monitored and kept off the road when impaired.
Who Legally Needs An Interlock Device?
In Australia, alcohol interlock devices are legally required for certain drink driving offenders as part of state-based interlock programs. These laws aim to reduce repeat offences by ensuring that individuals with a history of high-risk behaviour can’t drive under the influence again.
You may be legally required to install an interlock device if you:
- Are convicted of high-range drink driving offences
- Commit repeat drink driving offences within a specific period
- Refuse to provide a breath test to police when requested
- Are found guilty of mid-range drink driving in some states (e.g. NSW for first-time offenders over 0.08)
- Are court-ordered to enter an alcohol interlock program
Each state and territory has slightly different rules regarding eligibility and duration.
If you’re unsure whether an interlock applies to you, it’s best to seek legal advice or check your state’s transport authority website. Penalties for failing to comply can include licence suspension or extended disqualification.
How Long Do You Need An Interlock For?
The length of time you’re required to have an interlock device installed depends on the nature of your offence and the laws in your state or territory. Generally, interlock periods range from 6 to 24 months, though more serious or repeat offences can lead to longer durations.
For example, in NSW, high-range or repeat drink driving offenders are often subject to a mandatory interlock period of at least 12 months, while Victoria may impose periods of 6 to 48 months depending on the offence.
It’s also important to note that compliance plays a major role. Any violations—such as failed breath tests or missed servicing—can result in extended interlock periods or delays in having your full licence reinstated.
Each state has its own guidelines, so it’s essential to follow the conditions closely and ensure the device is properly maintained. Once the program is completed successfully, you’ll typically be eligible to regain your unrestricted licence, but only after demonstrating consistent, alcohol-free driving behaviour during the interlock period.
Why Choose Guardian Interlock?
Guardian Interlock is a leading provider of alcohol interlock devices, trusted by drivers and authorities across Australia. As an accredited provider in every state and territory, Guardian helps you meet your legal obligations with ease, from installation to program completion.
With Guardian, you can expect:
- Accreditation Australia-wide: approved in NSW, VIC, SA, WA, TAS, ACT, and NT
- Easy installation: quick, professional fitting at service centres near you
- Ongoing support: helpful guidance, servicing reminders, and responsive customer care
- Seamless compliance: automatic reporting to authorities as required
- User-friendly devices: clear instructions and reliable performance
Reach Out To Guardian Interlock Today!
Whether you’re completing a court-ordered interlock program or complying with a state-based requirement, Guardian makes the process smoother. Their focus on support and simplicity means you can get through your interlock period without added stress—while staying safe and compliant on the road.
Email admin@guardianinterlock.com.au or call 1300 881 005 today to get started with your alcohol interlock program.
