Finally, this report analyzes the issues surrounding what many experts consider to be the single most effective motorcycle safety strategy, the requirement that all motorcyclists wear a helmet that complies with federal safety standards (universal helmet law). Motorcycle Fatalities are an Increasingly Significant Proportion of all Motor Vehicle Fatalities

The number of motorcycle fatalities has more than doubled over the past decade, from 2,176 in 1996 to 4,810 in 2006. Part of this increase can be attributed to a significant growth in the number of motorcyclists. According to the motorcycle industry, annual sales of on-highway motorcycles have tripled in the past decade. But as Table 1 shows, the rate of increase in fatal motorcycle crashes (116%) and rider fatalities (115%) is almost double the rate of increase in the number of motorcycles registered (63%). As a result of both vehicle characteristics and operator characteristics, the rate of motorcycle involvement in fatal crashes, both by the number of registered vehicles and by VMT, is several times that of passenger vehicles (see Table 2 ). As noted above, the number of passenger vehicle traffic deaths has declined over the past decade, while the number of motorcycle deaths has been increasing. In light of this, DOT has declared that motorcycle fatalities are currently the nation's greatest highway traffic safety challenge. NHTSA has detailed information about the characteristics of fatal crashes, but without detailed information on the population of motorcyclists who are exposed to the same risks but do not experience fatal crashes, the significance of the factors observed in fatal crashes cannot be established. Since that time there have been significant changes in the characteristics of the motorcycle rider population, the highway vehicle fleet mix, and the highway environment. Additional Sources of Motorcycle Safety Recommendations

		National Agenda for Motorcycle Safety (NAMS)

In 2000, DOT published the National Agenda for Motorcycle Safety (NAMS), a plan for improving motorcycle safety. Selected Options for Improving Motorcycle Safety

There are two main approaches to reducing motorcycle crashes and fatalities: reduce the number of crashes (through rider skills training and reductions in risky behaviors, educating motorists to be aware of motorcyclists, improvements to road design, and improvements to motorcycle stability) and reduce the deadliness of motorcycle crashes (through improvements in rider protective gear, reduction in roadside hazards, and improvements in the crashworthiness of motorcycles). Universal Helmet Law

Head injuries resulting in injury to the brain are the leading cause of death in motorcycle crashes. NHTSA has found that motorcycle helmets are the single motorcycle safety measure whose effectiveness has been specifically proven, and that requiring riders to wear helmets is a relatively low cost measure which can be implemented by a state passing a law requiring all motorcyclists to wear helmets and is relatively easy to enforce. Rates of Motorcycle Helmet Use

The most recent survey of helmet use showed that only 58% of motorcyclists were wearing a DOT-compliant helmet in 2007, up from 51% in 2006 but down from 71% in 2000. Twenty states, the District of Columbia, and Puerto Rico, have universal helmet laws (see Table 3 ). In 1976, Congress repealed the penalty for failure to have a universal helmet law. In 1995, Congress repealed that provision. Subsequent studies have continued to support these findings. Proponents of universal helmet laws include NHTSA and numerous groups representing the transportation safety, medical, law enforcement, and insurance communities.
The U.S. Department of Transportation (DOT) has declared that motorcycle fatalities represent the nation's greatest highway traffic safety challenge. Over the past decade, the number of passenger vehicle auto deaths has declined slightly, even as more drivers have been driving more vehicles more miles. But the number of motorcycle fatalities has more than doubled over the past decade, to 4,810 in 2006ârepresenting 14% of all passenger vehicle occupant deaths. Annual motorcycle fatalities are now more that double the number of annual deaths from aviation, rail, marine, and pipeline accidents combined. While part of this increase can be attributed to an increase in the number of motorcyclists, the number of fatalities is increasing at a greater rate than the overall increase in ridershipâthe number of fatalities has increased by 116% in the past decade, while the number of registered motorcycles increased by 63%. The increase in fatalities has continued in spite of the National Highway Traffic Safety Administration (NHTSA)'s publication in 2000 of the National Agenda for Motorcycle Safety, a plan for reducing motorcycle accidents and fatalities. The motorcycle industry expects the growth in motorcycle sales to continue, so the total number of motorcycle fatalities may continue to increase, barring new safety measures.
A clear understanding of the factors involved in motorcycle crashes is needed in order to develop effective safety measures to reduce the rate of motorcycle crashes. NHTSA has detailed information about the characteristics of fatal motorcycle crashes, but not about causes of the crashes. The last major study of the causes of motorcycle crashes in the United States was published in 1981. Since that time, the motorcycle rider population and the characteristics of both the motorcycle and passenger vehicle fleet have changed. Congress has authorized another major study of the causes of motorcycle crashes; the results of this study are expected in 2010. Congress has also authorized a motorcycle safety grant program promoting rider education and training and motorist awareness of motorcyclists, and established a Motorcycle Advisory Commission to advise DOT on infrastructure issues of concern to motorcyclists.
According to NHTSA, the single most effective safety measure to reduce motorcycle fatalities is to wear a helmet that meets DOT standards; such helmets are estimated to reduce fatalities by 37%. Helmets also reduce the severity and cost of injuries received in motorcycle crashes. Twenty states and the District of Columbia currently have universal helmet laws requiring all motorcyclists to wear helmets; most other states only require minors to wear helmets. The National Transportation Safety Board has recommended that all states adopt universal helmet laws. Universal helmet laws have been controversial. Congress has twice adopted and then repealed incentives promoting universal helmet laws, most recently repealing the incentives in 1995. These incentives were effective in getting states to adopt universal helmet laws, and the laws proved effective in promoting helmet use. After each repeal, the number of states with universal helmet laws declined. Surveys indicate that 58% of motorcycle riders wore a helmet in 2007, up from 51% in 2006, but down from 64% in 1996. This report will be updated as warranted.