PHOENIX - Tucson could eventually be forced to shut down its arguably most controversial red-light camera at North Oracle and West River roads, under a bill approved by the state House Monday.

The legislation would require cities seeking to install or maintain the cameras on state highways to prove that they are "necessary for the public safety of this state." North Oracle Road is a part of state Route 77.

Existing photo enforcement sites could remain for now. But HB 2477 would require the Arizona Department of Transportation to review safety data every three years. If that review does not show any improvement in safety at that site because of the cameras, ADOT can force the city to remove them.

The legislation, approved 47-12, is a compromise of sorts between lawmakers who want to outlaw photo enforcement entirely and those who say these decisions should be left to the cities.

The legislation offered by Rep. Debbie Lesko, R-Glendale, would not bar cities from putting speed or red-light cameras on their own streets.

But state highways - anything with a route number - are within the purview of ADOT, and Lesko said she wants to use that leverage to ensure the devices are being installed to reduce accidents, not simply to generate revenues.

The state itself used to have photo radar to catch speeders on many state highways, installed in 2009 during the administration of former Gov. Janet Napolitano, who once estimated the units would generate $90 million in citations to help balance the budget. But in the first year they brought in just $37 million, and in 2010 they were removed after Gov. Jan Brewer let the contract with the operator expire.

The red-light camera at North Oracle and West River was installed in March 2008, the fourth of what eventually became eight such installations.

Tucson's cameras have been the subject of much controversy, particularly the one at Oracle and River, where drivers are often confused about where the intersection begins and ends because of the sweeping line of the curbs.

That controversy prompted prior bills to force cities to lengthen the time of yellow lights, amid charges Tucson had set them so short solely to generate traffic citations.

Because it is a state road, the Oracle Road installation required ADOT approval, which is where Lesko figures she can get some leverage by requiring cities to prove that the cameras actually improve safety.

"ADOT doesn't currently have a way to stop cities from placing photo radar cameras on state highways," she said. "My legislation will allow them to do that if they deem there's not a public safety reason to put a photo radar camera on a state highway."

ADOT spokesman Tim Tait acknowledged that his agency's powers are limited.

"From ADOT's perspective, the permitting process for these cameras is a matter of local control and is handled as routine," he said. Tait said it is up to each city to make an application for camera installation based on its own assessment of law enforcement needs.

"If the city completes all of the permit requirements, the permits are granted," Tait said. He said the only issue now for ADOT is to ensure that any installation complies with engineering safety standards.

Lesko said her legislation does not specify what a city would have to prove. "It will be up to ADOT to come up with criteria," she said.

But she said her legislation requires the agency to look at the number of vehicles passing through the site and what percentage of them are breaking state law. It also requires ADOT to review reports of traffic accidents on that stretch of road.

She wants proof the cameras are doing their job.

"Not only does it say you have to prove there's a public safety reason to place a photo radar camera on a highway, but you also have to show there's some improvement in public safety," she explained.

Lesko agreed providing a before and after analysis might be more difficult in cases where the cameras already are in place. She said, though, it would be up to ADOT to decide how to analyze the data available to determine if their presence makes sense.

Besides Tucson, ADOT has agreements with Chandler, El Mirage, Globe, Superior, Show Low, Star Valley and Prescott Valley for photo enforcement, and Sierra Vista and Casa Grande are seeking to install cameras.