In recent decades, American state and local highway officials have built wide streets and roads designed primarily to accommodate high-speed automobile traffic. However, such high-speed streets are more dangerous for pedestrians and bicyclists than streets with slower traffic, and thus fail to adequately accommodate nondrivers. Government officials design streets for high-speed traffic partially because of their fear of tort liability. An influential street engineering manual, the American Association of State Highway and Transportation Officials’ Green Book, has generally favored the construction of such high-speed streets, and transportation planners fear that if they fail to follow the Green Book’s recommendations, they are more likely to be held negligent if a speeding driver is injured on a street designed for relatively slow traffic.
Changes in the Green Book may ameliorate such design considerations in the future.