Flashing your headlights to warn other drivers of a speed trap might be illegal, but a US court has now ruled it is also free speech.
Florida Judge Alan Dickey has agreed with a plaintiff who sued police for issuing him a ticket for flashing his lights to warn drivers of a speed trap, saying that the laws didn't apply to people who use their headlights to communicate.
He also broadened his ruling to say that using headlights to communicate is free speech protected by the US Constitution. In Australia, flashing your headlights within 200m of an oncoming vehicle is considered dangerous as it dazzles the approaching driver and attracts a low-level fine. In Queensland the penalty is $40 and one demerit point.
University of Queensland tort specialist Kit Barker says Australian drivers would have no "free speech'' defence against a fine.
"The only constitutional right to free speech in Australia is an implied freedom to communicate on governmental and political matters,'' he says.
"We do not have the same constitutional protections for speech as in the US and there is no equivalent to the 1st Amendment.
"Since flashing your lights at others would not be counted as political or governmental speech even if it was considered speech, it is most unlikely that it would fall within the ambit of our (implied) constitutional protection."
Barker says there is also no defence in arguing that flashing your lights aids police in the execution of their duties by preventing other drivers from speeding.
"Factually, this is unlikely to be provable. Who, in all honesty, flashes lights to assist people to slow down rather than avoid detection?'' he says.
However, Barker says the basis for charging drivers with flashing their lights would be thought of as "culturally ludicrous'' in the UK where a quick flash of the lights is used for several reasons.
"I assume the argument is framed in terms of traffic safety, but there can surely be no universal rule if this is so,'' he says.
"Would it also be against the law to flash your lights to warn oncoming traffic of an accident?
"If not, then why is it a traffic safety offence to warn oncoming traffic to slow down?''
Our laws ban the use of high beam within 200m of another vehicle or in a situation that could "dazzle'' another road user. However, RACQ road safety spokesman Steve Spalding says police do have the discretion to apply the rules depending on the circumstances.
"We would expect a motorist, and the police, to use their discretion in situations where the intent was to alert other road users to a potential safety hazard such as a crash or similar type of incident,'' he says.
Truck safety campaigner Rod Hannifey, who has set up TruckRight.com.au to educate truckies and other road users, advises motorists who have been passed by a truck to flash their lights when it is safe for the truck to pull back into the left.
OUR VIEW
Carsguide says surely a quick flash of the headlights will not dazzle other motorists but alert them to a danger, hazard or even if the other motorist has forgotten to turn on their headlights. That's more than freedom of speech; it's basic communication.
We also believe that flashing your lights to warn other drivers of a speed trap has the beneficial result of slowing traffic at a crucial spot that police have deemed dangerous enough to warrant a speed trap.
That is, of course, unless the speed trap is located at the bottom of a hill, in which case, flashing your lights serves to prevent a transfer of wealth from the private to public sector. However, barging up behind someone and holding high beam on is not freedom of speech, but road rage - pure and simple - and just not on.