The New York Times has run a piece examining the many problems with red light camera systems, focusing on the increase in rear end accidents that the devices create. The newest item mentioned is a forthcoming paper that quantifies the claimed decreases in angle crashes and increases in rear end collisions. The camera supporters say the one type of accident is better than the other, although the researchers' paper only finds a "$28,000 to $50,000" yearly benefit per camera. Compared to the millions some individual cameras take in yearly, it doesn't seem compelling evidence of a benefit.

But studies to be presented at a transportation conference next week in Washington by two researchers, Forrest M. Council and Bhagwant Persaud, reach a more nuanced conclusion. They found that rear-endings had gone up nearly 15 percent after cameras were installed in seven cities, with injuries from such accidents up 24 percent. Right-angle crashes declined by 24 percent, with injuries down nearly 16 percent. Weighing the economic impact and severity of injuries, they found the overall effect positive.