Traffic light cameras, if you don’t already have them, are coming soon to a town near you. Their advocates claim that stoplight cameras catch red-light runners, deter them from their dangerous habit, and thereby save lives. It seems like a reasonable argument, but several research studies have blown that argument out of the water. The fact is, traffic light cameras actually make the roads less safe than they were before.
Traffic Light Cameras Cause Rear-End Collisions
Fear of being caught by a red-light camera leads many drivers to slam on their brakes as soon as the light changes from green to amber. That fear is understandable, because at many of the affected intersections the amber-light time has been deliberately reduced to increase the number of tickets that can be written. (No prize for guessing why!) Federal transport regulations require amber-light times to be in the region of 3.5 to 4 seconds – an inconvenient obstruction to revenue-generation that many municipalities choose to ignore.
Thus, an investigation by The Washington Post found that red-light cameras in Washington, D.C. raised over $32 million in revenue but led to an increase in the number of accidents. The Virginia Transportation Research Council acknowledged that while accidents caused by red-light runners did decrease, the overall number of accidents increased. And on the West Coast, traffic light cameras in Portland, Oregon caused rear-end collisions to rise by 140%.
Traffic Light Cameras Can’t Solve the Real Problem Anyway
Interestingly, a study by the University of Central Florida found that the injury rate from red-light running had been dropping steadily even without red-light cameras. The number of such accidents had fallen by over a third in just ten years, accounting for only 4% of traffic fatalities. For anyone who has driven in Florida’s burgeoning urban areas, this finding is counter-intuitive, to say the least, but it just goes to show that we need to know how big a problem really is before declaring war on it. As if that wasn’t enough to weaken the case for red-light cameras, the UCF study went on to find that red-light running could be reduced by as much as 74% simply by improving intersection markings, with no increase in rear-end collisions.
But the length of the amber light is the most important factor here. The Texas Transportation Institute found that red-light running fell dramatically when amber times were lengthened. It also exposed the core fallacy underlying the camera approach. For while most camera tickets were issued within one second of the light turning red, most T-bone accidents – the ones we’re really trying to prevent – occur five seconds after the light turns red. The people causing these accidents are dangerous in a much more fundamental way than mere “amber gamblers,” and ticketing drivers who miss the light by half a second doesn’t reach those people at all.