The mobile speed camera targeting Dubbo drivers on Wingewarra Street was likely to have recorded inflated speeds, a former NSW police highway patrolman also told the Daily Liberal.

The vehicle carrying the speed camera should have been parallel to the bitumen, closer to the kerb and on a straight segment of road to gauge accurate readings the former officer, who asked to remain anonymous, said.

The NSW Roads and Traffic Authority, which out-sourced the operating of the cameras brought in this year to private contractors, rejected the claims.

But Roy Zeger and Scott Cooper, two specialists who have built careers out of fighting speeding fines, backed the former cop.

“The ex-highway patrolman is right. The procedure followed here is incorrect, that is 100 per cent. It definitely cannot be parked there because a speed camera can not be parked on a slope,” Mr Zeger, from Australian Radar Detection Services, said.

“Speed cameras shall not be set up on a bend. This case it is quite noticeable that the device is set up on a bend.

“Basically where that speed camera is located not one speed ticket is valid.”

After forwarding the photographs to the RTA it said the vehicle was “parked in accordance with parking procedures”.

According to its website contractors were required to set up mobile speed cameras “in accordance with operating procedures” while a letter from assistant police commissioner John Hartley urging the then minister Tony Kelly to utilise the mobile cameras said they did not require “any skills beyond the correct parking and start-up procedures’’.

The RTA would not provide the operating procedures to the Daily Liberal despite repeated requests however it did say “the vehicles (were) deployed to ensure safe and accurate operation of the enforcement systems”.

The former policeman who first contacted the Daily Liberal said it seemed strict requirements that police were legislated to follow when targeting speeders had been “relaxed” for private contractors.

A camera not parallel to the road could “add a couple of kilometres per hour (km/h) to the target vehicles speed,” if it was aimed to the left and “out to the right it can subtract a couple”. The hill in Wingewarra Street could add 10 per cent to a car’s speed reading, he said.

“In this photo there is a little hint, the front wheels are turned in to the left just slightly, you can just see it. Is there a performance requirement included into their contract?” He said.

“Don’t get me wrong, I am totally committed to road safety but be fair dinkum about it. If I was anyone receiving a fine for a couple of km/h over the limit I’d take a closer look at this photo and the questions, was I or was it a slight of hand?”

Mr Cooper from Speeding Fine Consultants agreed mobile speed cameras should be parallel to the lanes and parked on “flat level ground on the same plane as the roadway”.

“In NSW the police rules say they should not be parked on bends. That’s the police’s own rules. These people are not above police rules,” he said.

Mr Zeger, who described himself as a forensic police traffic radar consultant, said the numerous reflective objects surrounding the camera on Wingewarra Street would “influence the readings”.

“I am wondering when they are going to wake up to this. They haven’t been operating long but they haven’t done their homework.”

Mr Zeger also raised the ugly possibility of contractors flouting the procedures to raise more revenue through increased fines.

“In the US where I’ve just been doing a study on their (speed cameras) a lot of counties got rid of (private contractors) for that reason. What the public doesn’t know allows the operator of the device to get away with and hence the revenue raising hypotheses,” he said.