Red light cameras significantly increase the risk of crashes at intersections, according to a new study released in the United States.

Researchers at the University of South Florida found that cameras increased crashes and related injuries because drivers were slamming on their brakes to avoid fines, causing rear-end accidents.

They also claim that some red light camera operators in the US have shortened the time that a light flashes orange in an attempt to increase revenue.

“Insufficient (orange) light timings can create a dilemma zone where the distance is too short to stop, yet proceeding into the intersection results in running a red light,” the study says.

The study says a more effective solution would be to increase the amount of time an orange light is displayed and to have a short period when lights in both directions at an intersection are red.

Researchers have also accused insurance companies of pushing the technology because it drove up insurance premiums.

“The rigorous studies clearly show red-light cameras don’t work,” says lead author Barbara Langland-Orban, professor and chair of health policy and management at the USF College of Public Health.

“Instead, they increase crashes and injuries as drivers attempt to abruptly stop at camera intersections. If used in Florida, cameras could potentially create even worse outcomes due to the state’s high percent of elderly who are more likely to be injured or killed when a crash occurs.”

The report was carried out as the State of Florida considers law changes to pave the way for the widespread introduction of red-light cameras.

The study’s authors argue that the injury rate from red-light running crashes in Florida has dropped by a third in less than a decade without the use of cameras.

It found that traffic fatalities caused by red-light running account for less than 4 percent of the state’s yearly traffic deaths.

It points to similar studies from North Carolina, Virginia and Ontario which show that cameras have led to more crashes and injuries, as well as increased crash costs.

The Florida research says that studies that advocated the use of red light cameras contained major “research design flaws,” such as incomplete data or inadequate analyses and were conducted by researchers with links to the Insurance Institute for Highway Safety.

The IIHS, funded by automobile insurance companies, is the leading advocate for red-light cameras.

The study says that insurers can profit from red-light cameras because they charge higher premiums if policy holders incur traffic fines.