Red-light enforcement cameras have saved lives in many cities, a new study says, but maybe not in Raleigh.
Fatal crash rates involving red-light runners fell after the cameras were installed in most of the 14 large cities studied, but the citywide death rates climbed in two - Raleigh and Bakersfield, Calif.
Raleigh uses the cameras at only 15 intersections, in a sprawling city where about 600 intersections have traffic lights.
Earlier reports have credited the cameras with sharply reducing injuries and serious crashes at those 15 intersections. But the new study suggests that Raleigh's few cameras haven't made a dent in overall crash rates across the entire city.
The Insurance Institute for Highway Safety study, released Tuesday, credits cameras with saving 159 lives in the 14 cities over five years by encouraging drivers to be more careful at intersections.
"I think when people know the law is being enforced, they're more careful when they approach intersections," said Adrian Lund, president of the Virginia-based institute, which is funded by the auto insurance industry. "It's important that they make this a community-wide thing, and not just do it at a few intersections."
The study compared fatal red-light crashes between two periods - 1992-96 and 2004-08 - for large cities with and without cameras. The per-capita crash count dropped by 35 percent for the cities that installed red-light cameras after 1996. The rate also fell for cities without the cameras, but only by 14 percent.
Against the trend
Raleigh's numbers went in the other direction.
Fatal crashes involving red-light runners, when compared per-capita to account for population growth, increased by 99 percent in the same period. The city's population increased by about 50 percent, and the number of fatal crashes grew from three to nine.
And when fatal crashes at all signal-equipped intersections in Raleigh were counted - six in 1992-96 and 24 in 2004-08 - the rate increased by 165 percent.
Mike Kennon, the city's transportation operations manager, said the new study suggests Raleigh could save more lives with cameras at more intersections.
"We have always had a very low number of cameras," Kennon said. "We target them at intersections that have had a lot of T-bone crash problems. A lot of those other cities have dozens of cameras. But in every intersection where we've put a camera, we've seen a substantial decrease in crashes."
Lund noted that Bakersfield and Raleigh grew fast over the past two decades, adding more land and population than other cities studied. He said it was hard to account for Raleigh's trend, and he suggested that the death count would have been worse without the red-light cameras.
Deadly T-bone crashes
Forrest Council, a senior researcher at the UNC Highway Safety Research Center in Chapel Hill, said red-light cameras have been shown to reduce crashes that cause serious injuries.
Council studied seven cities and found that T-bone crashes - the kind caused by running a red light - fell sharply at intersections with red-light cameras. There was, however, an increase in rear-end collisions, which cause less injury and damage than T-bone crashes.
"If you want to look at the impact of the cameras, you have to look specifically at those locations," Council said. "It's difficult to assume you're going to have a major effect on a city's total intersection safety problem with cameras at just a few intersections."
firstname.lastname@example.org or 919-829-4527