American commercial streets are often designed almost exclusively for cars; streets are often as many as eight or ten lanes wide, lengthening pedestrian trips and encouraging motorists to drive at speeds unsafe for pedestrians.
American commercial streets are often designed almost exclusively for cars; streets are often as many as eight or ten lanes wide, lengthening pedestrian trips and encouraging motorists to drive at speeds unsafe for pedestrians.
In part, the anti-pedestrian design of American streets is a result of transportation planners' perceptions of American tort law. When a road user injured in a car crash sues a government or its employees for negligent street design, courts may rely upon the "Green Book", a set of engineering guidelines drafted by the American Association of State Highway and Transportation Officials (AASHTO). And because AASHTO's street design rules have historically favored wide streets built to accommodate high-speed traffic, transportation planners sometimes believe that in order to avoid liability, they must do the same.
In fact, the Green Book no longer dictates the creation of high-speed streets, for two reasons.
First, in the majority of states, government entities and their employees are not liable for negligent decisions arising from "discretionary" government activities. As a rule, a government decision is "discretionary" when "broad policy factors were involved in reaching the allegedly negligent decision." (1) Such "broad policy factors" are certainly present where government officials are consciously choosing to weigh the policy of protecting pedestrian safety against the policy of encouraging fast driving.
For example, courts have held that government decisions related to street width are discretionary. In Stewart v. State, the Washington Supreme Court wrote: "The decision to build the freeway, the decision to place it in this particular location ... the number of lanes- these decisions involve a basic governmental policy" and are thus discretionary (2).
Discretionary immunity applies even when government has chosen to ignore Green Book guidelines. For example, in Schmitz v. City of Dubuque, the Iowa Supreme Court noted that a bike trail violated AASHTO standards, but nevertheless went on to address the merits of the city's discretionary immunity defense.(3)
Second, the Green Book itself does not require anti-pedestrian street design. The Green Book states that "its guidelines are not intended to "supercede the need for the application of sound principles by the knowledgeable design professional"(4) and the U.S. Court of Appeals for the Eighth Circuit has accordingly pointed out that the Green Book's provisions "are guidelines and are not mandatory."(5) Thus, AASHTO guidelines are not mandatory even in states rejecting discretionary immunity.
More importantly, the Green Book's guidelines, even if followed to the letter, are less anti-pedestrian than in the past. In its Foreword, the 2004 Green Book states: "[e]mphasis has been placed on the joint use of transportation corridors by pedestrians, cyclists and public transit vehicles. Designers should recognize the implications of this sharing of the transportation corridors and are encouraged to consider not only vehicular movement, but also movement of people"(6)
In particular, the Green Book states that in designing "local" residential streets, a streetbuilder's "overriding consideration is to foster a safe and pleasant environment whereas the convenience of the motorist is secondary." (7)To protect pedestrians, the Green Book actually recommends sidewalks even in rural and suburban areas (8).
And even Green Book guidelines regarding heavily trafficked streets are no longer oblivous to pedestrians' interests. According to the 2004 Green Book, arterial streets (the busiest type of street) may be as narrow as four lanes (9), and intermediate-volume collector streets (which connect residential and commercial areas) should typically be two lanes wide (10).
In sum, the Green Book no longer requires transportation planners to build six-lane monster streets; thus, a transportation planner reluctant to build such streets no longer must worry about losing a lawsuit.
1. Breed v. Shaner, 562 P. 2d 436, 443, 57 Haw. 656, 667 (1977) 2. 92 Wash. 2d 285, 294, 597 P. 2d 101, 106 (1979). See also Mitchell v. State, 108 A.D.2d 1033, 1035, 486 N.Y.S.2d 97, 99 (N.Y.A.D. 3 Dept. 1985) (road adequately designed "despite its narrowness").
3. 682 N.W. 2d 70 (Iowa 2004). The court went on, however, to hold that the government's decision was based solely on cost and was thus not discretionary.
4. 2004 Green Book at xliii.
5. 486 F.3d 1030, 1033 (8th Cir. 2007).
6. 2004 Green Book at xliv.
7. Id. at 390.
8. Id. at 357-58, 436.
9. Id. at 473.
10. Id. at 433.

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