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A friend of mine today showed me an infringement notice for speeding, noted by a fixed speed camera.

It was for doing 75kmh in a 70kmh area at 5.20pm. Fine $30.

I understood that Police allowed a margin of up to 9kmh - obviously not!

Helen

From the "Ask Jack" archives - 28 September 2009

The 10km/h margin/tolerance you refer to only applies to police radars or laser guns, i.e. roadside enforcement, not unmanned speed cameras. It was originally introduced to allow for slight measurement inaccuracies in the equipment although they are much more reliable today.

The 'tolerance' for speed camera infringements is different as they are very accurate. Instead the police will only ticket the fastest 15% of drivers (provided they are over the limit). So you might not get a fine if the majority of drivers were faster, on the other hand you will if the majority drive at or below the limit. The fine your friend received is correct: speed offences up to 10km/h over the limit attract a $30 fine (between 11-15km/h over the limit = $80 and so on).

Our advice to motorists is to regularly check your speed. By (international) law, all car speedometers must overstate true speed by about 3-7%. So at a true speed of 75km/h the speedo on the car could have been indicating as much as 80km/h (although the accuracy can be negatively affected by incorrect tyre pressures or wheel sizes).

By the way, the 10km/h speed tolerance is only police policy and is not legislated, so they could change it at any time, although it would be unpopular if they dropped it.