The proposal, which would follow a similar take-no-prisoners approach by the Victorian government, has drawn criticism from senior highway patrol officers, who believe the margin for error is too small, The Sun-Herald says.
The reduced tolerances are part of a tougher stance on speeding adopted by the NSW government, which includes six mobile speed cameras appearing on Sydney streets from July 19.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Driving fines are expected to rise by $137 million in the next year, partially because of mobile speed cameras, the state budget reported.
The cameras, which can fine six drivers every second, will be set up in white Ford Territory vans operated by RTA-contracted company Redflex. Signs will inform drivers they have been "checked" after they pass the vans, which also shoot video.
One senior Sydney policeman told The Sun-Herald, on condition of anonymity, that a 4 km/h tolerance is so small that a new set of tyres or the width of a speedometer needle could land motorists on the wrong side of the law. He said some radars have an error margin of plus or minus 3 km/h, while most police allow a margin of 8 or 9 km/h at 60 km/h.
The RTA is responsible for the limit on fixed cameras, as well as those in the new mobile vans.
An RTA spokeswoman said: "The RTA does not discuss enforcement thresholds on road safety grounds." But she did not deny the hardline approach is being considered, the paper says.
