Urban form, health, and the law's limits.

Urban form, the law, and health are undoubtedly linked. However, nonlegal factors such as 20th-century reliance on the automobile as well as associated governmental actions and private investment choices have greatly influenced urban form, especially urban sprawl. The American system of federalism, with its traditional allocation of land-use legal authority to local governments, and resulting fragmented legal authority over causes and effects of urban sprawl, renders difficult legal efforts to reshape urban form. Legal frameworks and the dynamics and effects of urban sprawl are largely mismatched. Still, existing legal frameworks and modest legal reforms provide means to encourage or at least allow urban forms that are more conducive to health. However, the law will not easily transform urban form and deter urban sprawl.