Some 45% of Los Angeles' red-light camera tickets are currently unpaid, partly because holds are not placed on driver's licenses and vehicle registrations for unsettled photo enforcement infractions, Los Angeles officials said Wednesday.

The disclosure came as City Controller Wendy Greuel issued an audit finding the photo enforcement program bypassed some of the city's most dangerous intersections and is costing the city more than $1 million a year to operate, despite fines and fees that can exceed $500.

LAPD officials said they learned during the audit that the state Department of Motor Vehicles has not been forcing payment of delinquent red-light camera fines during license and registration renewals. Other types of unpaid citations typically must be paid before renewals are granted, noted Police Chief Charlie Beck, who appeared with Greuel at a news conference under a downtown red-light camera.

It was not immediately clear why red-light camera tickets would be treated differently, although one LAPD official noted motorists do not sign promises to appear in court when photo citations are issued. A DMV spokesman said he had to check into the matter.

Currently, the city has issued about 56,000 red-light camera tickets that are unpaid. About one-third of traffic tickets overall are unpaid, Beck said. Beck said his department is working with the courts and the DMV to correct the red-light camera glitch as part of a broader push to improve the program's cost efficiency and safety benefits.

Among other changes, Beck and Greuel said the city, which is planning to expand the program beginning next year, should focus camera enforcement on the most dangerous intersections in the city. Both noted that the current placement of cameras at 32 intersections was driven partly by politics and a desire to have at least one red-light camera in each of the city's 15 council districts.

"We should deploy them like any other officer" based on public safety needs, Beck said.

The audit also found that the LAPD had not developed data that conclusively shows the cameras have improved public safety. It noted that half of the intersections equipped with cameras showed no reductions in accidents in one study. Beck agreed better analysis is needed, but strongly defended the program, saying it has cut fatalities at the targeted intersections.

There have been no traffic deaths at the intersections since cameras were installed, he said. Based on previous trends, "we would have had 10 fatalities," he added. "This is why we were interested in red-light cameras in the first place."

Beck stressed that the program is not intended to make money. But he and other officials hope to improve the program's financial footing when a new contract to operate the cameras is issued next year.