Last summer, civil engineering professor Nicholas Garber and his colleagues received a query from Richmond: Could the researchers figure out, quickly, whether red light cameras have had any effect on car crashes?
Garber, who teaches at the University of Virginia, now finds himself in the middle of a political tussle over public policy and privacy that could result today in the House of Delegates' dismantling of efforts to shoot pictures of -- and fine -- red light runners from Fairfax County to Virginia Beach.
A sign warns motorists in Alexandria of the presence and reach of a red light camera at Gibbon and South Patrick streets.
(1998 Photo Lucian Perkins -- The Washington Post)
"My problem is, we are researchers who have to say exactly what the results are," Garber said.
Garber studied the best data available, from Fairfax County, and documented what for many is a counterintuitive finding: that the use of cameras at intersections resulted in more injuries. That's because while crashes from the side went down, rear-end accidents went up. His results, consistent with those of some other studies across the country, have poured fresh fuel onto the heated cost-and-benefit debate on the cameras in Virginia.
The problem is, transportation researchers, including Garber, say his study does not come to a conclusion on the most relevant scientific issue: whether motorists are safer with the cameras. That has left advocates sparring in Richmond with incomplete information, just as other proponents and detractors have in similar debates from California to Maryland. But a new federal study offers an answer to that question.
The cameras, which automatically photograph vehicles when they run red lights, were authorized by the Virginia legislature in 1995 and also are used in Alexandria, Fairfax City, Falls Church, Vienna and Arlington. The authorization expires June 30. Bills allowing jurisdictions to continue using the technology cleared the state Senate last month but face a hostile reception today in the House Militia, Police and Public Safety Committee. The cameras also are used in the District and Maryland.
Privacy advocates say the cameras are an invasion and unfair to motorists. Violators are fined as much as $50. Law enforcement officials argue that the cameras make the roads safer. Transportation researchers say red light running causes 100,000 crashes each year in the United States and about 1,000 deaths. In 2003, there were nearly 5,000 such crashes in Virginia, resulting in at least 18 deaths and more than 3,800 injuries, Garber said.
The comprehensive national study, funded by the Federal Highway Administration and presented last month, offers the most definitive scientific view of the cameras' overall safety implications and could color future debates.
Researchers scoured 17 international studies on the cameras looking for methodological shortcomings and pitfalls. Then the group of academics, transportation consultants and the Federal Highway Administration's safety research office analyzed data from programs in Montgomery and Howard counties, Baltimore, California and North Carolina.
They confirmed what many, though not all, previous studies had found: Right-angle crashes decrease, and rear-end ones go up, once the cameras are installed. That is largely because more accidents at camera locations occur as motorists abruptly stop before the intersections and fewer people cause accidents by speeding into intersections on the red.
They then tackled the even more nettlesome question of overall safety, which the Virginia study had posed but was unable to answer.
"The best measure of effectiveness is, what are you doing to the injuries and the severity of injuries," said John S. Miller, a Garber colleague and fellow researcher at the state-funded Virginia Transportation Research Council.
What the federal researchers came up with, ultimately, is a dollar figure.
By tracking the costs associated with different kinds of crashes -- including tallies of everything from car repairs and hospital bills to the value of lost quality of life for the seriously injured -- the researchers calculated that having the cameras saves society an average of $28,000 to $50,000 annually for each intersection with a red light camera.
Eduard Zaloshnja, a co-author of the federal study and a research scientist at the Pacific Institute for Research and Evaluation, based in Calverton, Md., was responsible for finding and analyzing detailed public health information and other data to determine the costs of different types of crashes.
Among the items included in the model are what Zaloshnja called the hard dollar costs -- such as government and insurance expenses, the value of productivity loss at home, and the value of time wasted by other motorists held up behind different types of crashes. He also put a monetary value on "loss of functionality," for example losing the ability to walk, write or watch television.
Physics explains much of the different results, he said.
"The guy hitting you on the side is speeding, because he's trying to beat the red light," Zaloshnja said. "The hit from behind can shake you pretty well, but you walk out of the thing without much damage. . . . And that's what our data shows, that [right-angle] crashes are much more expensive."