The law on drivers flashing their headlights to warn other motorists of police

Contrary to popular belief, there is no specific law that specifically bans Australian drivers from alerting other motorists that a police patrol or speed camera is nearby.

But drivers can still be stung with a fine if they follow motorists’ ‘secret code’ and flash their high beams at one another. 

A Sydney woman recently sparked discussion about the practice on Reddit, after posting that another driver had warned her a speed camera was ahead ‘for the first time in what feels like years’.

Flashing your lights at another driver is something of a legal grey zone. 

An Australian motorist posted to social media saying an oncoming car had flashed their headlights at her to warn a mobile speed camera was ahead

It is against the law to drive on the road with high-beam headlights if a car in front travels in the same direction within 200 metres.

It’s also an offence to flash high beams when another oncoming vehicle is within 200 metres.

In New South Wales, flashing high-beam lights in traffic carries a maximum penalty of a fine of $2,200. But police will usually only issue a penalty notice of $112.

That penalty would also result in one demerit point, though the same offence in Victoria could mean three demerit points off your licence.

Law firm Astor Legal said flashing other drivers could arguably earn a conviction as an example of hindering a police officer in the execution of their duty, or even perverting the course of justice, a serious offence carrying a maximum of 14 years in jail.

But it is regarded as difficult to prove in court that a car flashing headlights was actually an attempt to hinder police or pervert the course of justice.

One Aussie pointed out a simple loophole to get around the rule: briefly turning your low-beam headlights on and off instead of flashing your high beams.

It is not against the law to test your headlights by turning them on and off, no matter how close other cars are.

‘Everyone in western Sydney does this,’ one Aussie said on Reddit.

It was apparent from the Reddit debate that flashing fellow drivers to warn police are about happens all over Australia – and beyond

Speeding is the number one cause of fatal road accidents in Australia

A Queensland driver claimed he had flashed his lights at other drivers for 25 years, and had personal experience of police response to it.

‘I remember everyone used to do this. But then cops used to pull people over for flashing. But it was mostly harassment from the cops so they could deter people from warning others,’ they claimed.

Aussies discussing the ‘secret code’ were overwhelmingly in favour of the rebellious act, so long as it applies to speed cameras and not policing of other matters.

‘I think it’s a great thing. It represents somewhat of a comradery between motorists,’ one commenter said.

‘Everyone flashes around where I live. [Police are] always hiding behind a bush,’ said another.

‘An Auspost worker on a motorbike did it to me the other day. Absolute legend.’

Another claimed it was ‘unAustralian’ not to warn other drivers of speed cameras.

The response on reddit was overwhelmingly in favour of the rebellious act – so long as it applies to speed cameras and not policing of other matters

But a few commenters said they’d never warn other motorists that police were doing random breath testing ahead

But a few said they’d never warn other motorists that police were doing random breath testing ahead.

‘Yeah I don’t warn for RBTs, if they’re stupid enough to drive drunk then they deserve to be caught.’