Most drivers like to think they know the road rules—but some regulations barely register until you're suddenly slapped with a fine.

One particular law has been quietly catching out Aussies across the country, despite being on the books for years.

What seems like an everyday habit could actually land you in legal hot water—and you might not even realise it's happening.

Most Aussie drivers have bent the rules at some point—maybe you’ve ducked into a café, left the car running, or just popped into the servo for a minute.

But what many motorists didn’t realise is that this everyday habit has been quietly costing people hundreds, even thousands, in fines across the country.

The offence? Leaving your vehicle unsecured…and no, it’s not just about locking the doors.

The little-known rule costing Aussies thousands. Image source: Pexels/DENİZ ÇAĞLUSU

CCTV footage from recent incidents revealed just how easily a parked, unlocked car could become a target for thieves. With one video showing an alleged offender attempting to break into a vehicle, it highlighted why these laws were brought in—to reduce the risk of opportunistic crime and protect public safety.

But here’s the kicker: drivers can be fined simply for leaving windows slightly down or forgetting to lock the doors, even if they’re only away for a moment.

Sydney-based lawyer Avinash Singh called it ‘perhaps the most obscure road rule’.

‘Most drivers are completely unaware of it and are usually shocked when the police confront them and explain that they can be fined for leaving their windows and or doors unlocked,’ he said.

It turns out the offence isn’t as niche as some might think. Singh, Principal Lawyer at Astor Legal, confirmed that these fines weren’t just theoretical.

‘We have seen instances of police issuing fines for this offence. Reasonable police officers will sometimes issue a warning first, however, we have had people elect to go to court to challenge the fines,’ he explained.

‘The most common argument we see drivers making if they have been fined for leaving their windows or doors unlocked, is that the law is illogical and oppressive.’

While it might seem like bureaucratic overreach, the rule has a serious purpose behind it. Unlocked cars aren’t just at risk of being stolen—they can also end up being used in further crimes or dangerous situations, which authorities are keen to prevent.

There was a small exception tucked into the legislation for those trying to balance security with comfort—like when leaving a pet in the car.

‘The legislation provides a defence if you have a window rolled down less than two centimetres,’ Singh said. ‘If the window is rolled down any more than that, then you will be liable to be fined.’

That slight allowance might come as a relief to pet owners needing to leave their dogs some air—but it’s not a free pass.

Depending on where you were in the country, penalties varied dramatically.

In New South Wales drivers were required to lock their cars and secure the windows if they planned to move more than three metres away. The on-the-spot fine sat at $114, but if the case ended up in court, it could climb to $2,200.

In Queensland, it was illegal to leave a vehicle unlocked when more than three metres from it. Leaving the keys inside could see the fine balloon to $2,669, with the maximum penalty reaching $3,096.

Victoria had similar rules—vehicles had to be locked and windows secured when the driver walked more than three metres away. The fine there was $117, but court penalties hovered around $600.

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Western Australia’s laws specified that a car must be locked unless someone aged 16 or over remained inside. Their maximum penalty? Just $50.

Tasmania enforced the same three-metre rule, with a fine of nearly $200.

In the Australian Capital Territory, drivers were obliged to lock up and secure their vehicles unless someone 16 or older stayed behind.

Only South Australia took a different approach—drivers there weren’t legally required to lock their doors at all when stepping away from the vehicle.

This quietly enforced rule might be one of the country’s least known, but as fines continue to be issued—and in some cases, challenged in court—it’s becoming harder for drivers to plead ignorance.

Next time you hop out for a quick errand, double-check those locks…because the cost of forgetting might be more than just an inconvenience.

There is another road rule catching Aussie drivers off guard.

Watch the video to save up to $6,000 in fines.

Source: Youtube/Yahoo Australia​

Key Takeaways

• Drivers across Australia have been fined for leaving their vehicles unlocked or windows slightly open, even briefly.
• Sydney lawyer Avinash Singh described it as ‘perhaps the most obscure road rule’, with some cases ending up in court.
• The rule aims to reduce car theft and related crimes, though a window can be left open less than two centimetres in most states.
• Penalties vary by state—from $50 in Western Australia to over $3,000 in Queensland—with South Australia being the only exception.

Have you ever been fined for something you didn’t even know was against the rules? Let us know your experience in the comments.

 

[Greg350]

More common sense that alludes people.

 

[7777]

These fines make total sense. You have your wallet, your glasses , your handbag, your laptop, your shopping that contains expensive clothes, important documents, or electronic toys or Adidas footware and the list goes on, all scattered in the back seat of your car. And so, are you going to take all these items with you when you step out of your car for a brief moment. Dont forget, sometimes one has to wait in que for a while until fuel is paid at the service station. Or we might get side tracked with a phone call on our mobile phone, while mailing a letter at a post office. It only takes minutes for the car door to be opened, and thieves to help themselves to your important and expensive items, and yet it also only takes a few seconds to turn the ignition off, press the window button close and lock the car door to safeguard everything in your car. Clearly, this rule has been made, as a result of so many police reports of stollen items from an unlocked car and opened windows. Then there are daily claims for stollen items from a car, that have been made to car insurance companies, by people claiming that they only stepped out of their car, for a brief moment and not locked their car door or window.
Be mindful, be smart, take those extra few seconds to close your car windows, turn your car off and lock your car door, you will be safe as well as keep your wallet happy free from a fine.

 

[7777]

These fines make total sense. You have your wallet, your glasses , your handbag, your laptop, your shopping that contains expensive clothes, important documents, or electronic toys or Adidas footware and the list goes on, all scattered in the back seat of your car. And so, are you going to take all these items with you when you step out of your car for a brief moment. Dont forget, sometimes one has to wait in que for a while until fuel is paid at the service station. Or we might get side tracked with a phone call on our mobile phone, while mailing a letter at a post office. It only takes minutes for the car door to be opened, and thieves to help themselves to your important and expensive items, and yet it also only takes a few seconds to turn the ignition off, press the window button close and lock the car door to safeguard everything in your car. Clearly, this rule has been made, as a result of so many police reports of stollen items from an unlocked car and opened windows. Then there are daily claims for stollen items from a car, that have been made to car insurance companies, by people claiming that they only stepped out of their car, for a brief moment and not locked their car door or window.
Be mindful, be smart, take those extra few seconds to close your car windows, turn your car off and lock your car door, you will be safe as well as keep your wallet happy free from a fine.

 

[meighLeigh]

Admittedly, I live in South Australia, so am not so much in danger except when travelling. More, I live in a small seme-rural town, having come from a smaller, more rural community where locking cars, winding up windows etc is very rarely done. I always try to remember to lock the car when I go to 'the big smoke' (Port Lincoln) or any city - but we almost invariably have the dog with us (no show without Punch, after all!) so leave the windows down a bit.

Mind you, now we have one of these modern things that tells us what to do, and if any window is down a millimeter too far, the car bleats at us and won't lock. But it doesn't remind me to lock it in the first instance! I suppose that's the next new gadget for cars.

 

[GoodEnough]

Every time I see a headline about some obscure road law tricking people, I find that I already know about the law. How ignorant are some drivers?

 

[BruceC]

We had a van dumped in our street with the keys left in it..
When the police came they said it is not illegal to park in another street.
Also no offence had been committed by leaving the keys in the ignition.
Go figure.. lazy bloody policemen…

 

[bluesbrother]

Can't crack your windows (unless someone's in the car)? That law was obviously not made in a hot place. Glad police have more common sense or they'd book every car in every outdoor parking lot all summer.

 

[Viellarde]

More common sense that alludes people.

Same people who are shocked that their insurance claim is denied.

 

[7777]

We had a van dumped in our street with the keys left in it..
When the police came they said it is not illegal to park in another street.
Also no offence had been committed by leaving the keys in the ignition.
Go figure.. lazy bloody policemen…

Perhaps the van was stollen and used for illegal purposes and then just dumped. In that case the rule for leaving keys in the vehical, may not apply here. Primarily because theft and illegal activity connected to the vehicle, would most likely override the issue of the key that was left in the egnition issue.

 

[Littleboy8]

Can't crack your windows (unless someone's in the car)? That law was obviously not made in a hot place. Glad police have more common sense or they'd book every car in every outdoor parking lot all summer.

There’s a new grille for the window if you’ve got a dog travelling in the car stops the animal or kidlets from falling out the window or just want fresh air it was advertised on dr Harry’s show. Great idea

 

[midgemills]

I have heard that abandoned cars sometimes are a problem near airports. Overseas tourists buy a cheap car to use here and then dump them with the keys for anyone else to use. They then fly out. Not sure of the protocol for legally claiming one.