Cary, N.C. — A Cary man claims that the formula used to set the length of yellow lights in town is flawed, which he says compromises safety and leads to tickets being issued unfairly at intersections with red-light cameras.

Brian Ceccarelli said he received a citation in the mail last year when a red-light camera caught him running a red light at Cary Towne Boulevard and Convention Drive. He said the incident frustrated him so much that he is crafting a potential class action lawsuit challenging the length of yellow lights.

"The shorter it is geometrically increases the number of people running the red light," Ceccarelli said.

The timing of the caution light is supposed to be based on the speed limit, the size of the intersection and a safe distance to stop.

Ceccarelli said that state Department of Transportation equations show the yellow light at Cary Towne Boulevard and Convention Drive should last 4.5 seconds, but he estimated it lasted only four seconds when he was ticketed.

"The half-second makes a big difference in the number of people that run a red light," he said. "It's a safety issue to everybody. By cutting short the yellow light, the town of Cary risks everybody's lives."

Cary traffic engineers and a physics professor at North Carolina State University dispute Ceccarelli's calculations.

Town officials said Cary's 17 red-light cameras are designed to prevent accidents. All yellow lights are timed to fit DOT safe-stopping standards, they said.

The red-light cameras in Cary generate about $100,000 in revenue from citations annually.

Ceccarelli said he believes the long-held yellow light timing calculations used across the country are wrong, and he said he hopes his lawsuit will bring the issue of traffic lights, math and safety to a head.

"They're all short anywhere from two to four seconds," he said. "They are not safe according to Newton's laws of motion."