A police video expert who has been given a ticket for driving too fast in Wrexham claims that speed guns are "inaccurate and unreliable".
The force say they have every confidence in the camera's reliability
Lee Tracey, 80, is asking North Wales Police for a copy of the video evidence so that he can challenge the booking.
Mr Tracey, a forensic imaging consultant from Oswestry, is hoping an organisation will take up the case.
North Wales Police said they had "complete confidence" in their officers' ability to use the cameras.
Although well past retirement age, Mr Tracey is still used as a consultant by West Midlands Police.
The pensioner claims he was "just meandering" on a Saturday afternoon shopping trip to Wrexham when he was booked last month for allegedly travelling at 39 miles an hour in a 30 mile per hour zone.
He has since been sent an official letter outlining the police offer of a £60 fine and three penalty points on his licence, but has refused to settle.
"If I was over the limit, I'd put my hands up immediately, but I don't think I was," he said.
But while challenging the reliability of hand-held laser guns, he said he had complete confidence in the accuracy of static speed cameras.
"If you're caught by one of them, then you're done and you might as well accept it and pay up," he said.
But, referring to hand-held guns, he added: "I could point one at a wall and make it show what speed that wall is doing," he said.
"I could show it travelling at 40 miles and hour or even 100 miles an hour.
"This is known to the engineering world, but the courts aren't interested because the purpose of these machines is to make to money, not to cut speeding."
Mr Tracey says that most drivers do not bother to challenge the evidence because of the cost involved, but he would like a test case.
"I'd like to take one of these hand-held cameras into court and show a judge, sitting on the bench, that he's doing 80 miles an hour."
Mr Tracey said he had asked North Wales Police to provide video evidence to support the case against him, but they had replied that they were not obliged to do so.
Chief Superintendent Geraint Anwyl, from the operational support division at North Wales Police, said officers were trained in the effective use of these devices.
"I have every confidence in their ability to record the speeds of moving vehicles.
"However, as this matter is currently awaiting court proceedings, it would be inappropriate to comment further."