Can we just call speed and red-light cameras what they are? Short-term revenue generators.

Or maybe that's just too politically unpalatable. Sure, the Insurance Institute for Highway Safety released a study in February that showed traffic cameras reduced fatalities, but it's the amount of revenue the cameras produce that drives their proliferation and locations.

As the Star's Rob O'Dell and Jamar Younger reported Monday, revenues and citations from speeding and red-light cameras drop precipitously once drivers know where the cameras are. But Pima County is planning to add at least another camera on the northwest side, and Tucson Police Chief Roberto Villaseñor said the city is considering moving some cameras to new locations. Officials have said the cameras make intersections safer.

If the cameras have made intersections safer, then why move them? And more importantly, have the cameras made intersections safer? Local data appear mixed on that last question.

Between the city and the county there are 19 cameras - 17 fixed locations and two vans - to catch speeders and red-light runners across the metro area. But for the 10 cameras set up in unincorporated Pima County, the safety results are varied, O'Dell and Younger reported. Accidents decreased at five intersections, but increased at four camera locations and stayed the same at one other location.

What is conclusive, though, is that revenues from traffic cameras decrease over time. Take traffic camera citations from city intersections.

For 2009 when there were four cameras and two vans, there were 39,795 citations issued, which resulted in $4.67 million in total fines. In 2010, there were 27,394 citations issued for the whole year, which resulted in $3.77 million.

Ten months into the city's fiscal year for 2011, there were 25,862 citations totalling in $3.93 million in fines. But the only catch is, the city now has seven cameras and two vans.

"People learn," the city's Finance Director Kelly Gottschalk told O'dell and Younger. "They avoid the intersections or they are cognizant of the cameras."

For the year that will end June 30, revenues from photo radar is on track to be $3.2 million below city projections. Meanwhile for the coming fiscal year, Pima County is estimating revenue from speed cameras will drop by more than 54 percent.

There may be plenty of reasons to expand the program. The cameras might allow Tucson police to deploy more officers to neighborhoods and hard crime, as opposed to traffic duty. And as the recent Insurance Institute for Highway Safety's study suggested, there may be safety benefits that come with the cameras. But let's at least be honest about what's really driving the expanded use of these traffic cameras.

Arizona Daily Star