fects of this reversal on a national level (Cook and Tauchen, 1984; GAO, 1987). Without these data, it would have been necessary to try to obtain data for a large number of states and determine which data elements were comparable, a difficult task, or to rely on the accumulation of single-state studies, which by themselves are often unreliable because of small sample sizes. The research findings were instrumental in leading to federal legislation that influenced states to establish 21 as the minimum age for purchase of alcohol or to lose federal highway funds (Wagenaar, 1993). This policy is now in effect in all states and is credited with having saved 16,513 lives from 1975 through 1996 (NHTSA, 1996).
In 1966, legislation was enacted that marked a significant change in the nation's approach to reducing motor vehicle injuries. The National Highway Traffic and Motor Vehicle Safety Act authorized the federal government to set safety standards for new vehicles and equipment, and the Highway Safety Act of 1966 authorized the federal government to develop a coordinated national highway safety program. The two acts legislated, for the first time, a comprehensive national program addressing the human, vehicular, and environmental factors that lead to motor vehicle injuries. They allowed for the development of safety standards for new vehicles and equipment and also targeted human factors (e.g., driver fatigue, effects of alcohol on driving). In 1967, the National Highway Safety Bureau issued highway program standards that were to be adopted by the states, including requirements for driver education, driver licensing, alcohol countermeasures, school bus safety, and motorcycle safety laws. States had to report on annual progress and could be penalized by the withholding of federal highway funds if the programs were not implemented. Thus, many states enacted new safety programs and legislation to meet federal requirements.
The passage of the Highway Safety Act of 1970 established the National Highway Traffic Safety Administration (NHTSA) as the successor to the National Highway Safety Bureau. NHTSA was charged with the responsibility of reducing deaths, injuries, and economic losses resulting from motor vehicle crashes and had regulatory, surveillance, research, and programmatic responsibilities, a mission and charges that it continues to implement. Additionally, the Federal Highway Administration works to improve highway safety and has regulatory jurisdiction over the safety performance of interstate commercial motor carriers and those carriers transporting hazardous materials. The federal regulatory program is designed to raise vehicle and highway safety standards and, despite legal impediments (Mashaw and Harfst, 1990), has led to a vehicle fleet that is far more crashworthy than 30 years ago. Initial resistance to federal regulation of vehicles has gradually subsided, so that there is currently a more cooperative relationship between federal regulatory agencies and industry.