THE Roads and Traffic Authority is considering plans to reduce the amount of leeway given to speeding motorists to as low as 4 km/h, according to senior police.
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 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 tomorrow week.
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 was 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 had an error margin of plus or minus 3 km/h, while most police allowed a margin of 8 or 9 km/h at 60 km/h.
The RTA was responsible for the limit on fixed cameras, as well as those in the new mobile vans.
Drivers of some European cars will be particularly vulnerable, as their speedos are marked at 50, 70 and 90 km/h - not the 60, 80, 100 km/h on home-grown cars - and may not see the speed accurately with the needle between the lines.
"The width of some needles is equivalent to 3 km/h," the policeman said. "Then you have things like parallax error [when an instrument's read-out differs depending on the angle at which it's viewed].
"It's all about the ability of the punter to drive their car and to be able to clearly and precisely read their instrument. I'm an advocate for road safety but I'm also very wary of applying a standard to the general motorist that they can't possibly comply with."
An RTA spokeswoman said: "The RTA does not discuss enforcement thresholds on road safety grounds."
But she did not deny the hardline approach was being considered.
"Research has shown that even travelling a few kilometres above the limit increases the risk of a crash. Drivers are reminded they should always drive within the speed limit and could be fined for speeding by even 1 km/h over the limit."
But some police and safety experts believe the approach would breed drivers who watch speedos at the expense of other dangers on the road.
In the first five months of this year road deaths in Victoria rose 13 per cent on last year, and over the past five years the road toll in the state has not fallen as sharply as in NSW.
Asked to comment on the plan, NSW Assistant Police Commissioner John Hartley said: "That's the first I've heard of it. That's a policy decision for the RTA, and I'm not prepared to say anything until I've seen a proposal."
A little more than a year ago Roads Minister Michael Daley changed the demerit points system to make it more lenient for those who exceeded the speed limit by less than 10 km/h, saying: "We all find ourselves creeping over the speed limit. I don't think people should get smashed for that."
An RTA spokesman said the undercover mobile cameras had proven useful in Victoria. But the NSW opposition roads spokesman on roads Andrew Stoner questioned whether they were an ''effective speeding deterrent''. ''The Keneally government is using the state's tragically high road toll as an excuse to raise revenue from drivers instead of increasing the use of highway patrols,'' Mr Stoner said.
NSW Police Association president Scott Weber said his union was vehemently opposed to the RTA mobile cameras, saying ''nothing is more effective than high-visibility highway patrols to prevent and detect traffic offences, prevent accidents and reduce deaths''.
Mr Weber also questioned why it was the RTA and not police who had been issued with more resources.
Redflex Holdings has won the contract to provide and staff the cameras for the RTA, and will start snapping speeders from tomorrow week from the vans.
But the decision to staff the camera cars is controversial after a death in Arizona. Doug Georgianni, 51, a former professional golfer, was killed in a drive-by shooting while operating a Redflex camera on April 19 last year. As a result, the company has changed its operations and the cameras are no longer manned. Mr Georgianni's death was not the only violent incident involving camera operators in the US, but Redflex chief executive Graham Davie said the RTA had insisted drivers of NSW mobile speed camera vans would remain inside vehicles.
An RTA spokesman said the safety of operators was a priority and any offences against camera crews would be prosecuted. ''NSW Police is a key partner in the implementation of the mobile speed camera program. Anyone assaulting an operator or damaging a mobile speed camera vehicle faces significant penalties, including imprisonment.''