The following appeared in a health newsletter.” A ten-year nationwide study of the effectiveness of wearing a helmet while bicycling indicates that ten years ago, approximately 35 percent of all bicyclists reported wearing helmets, whereas today that number is nearly 80 percent. Another study, however, suggests that during the same ten-year period, the number of bicycle-related accidents has increased 200 percent. These results demonstrate that bicyclists feel safer because they are wearing helmets, and they take more risks as a result. Thus, to reduce the number of serious injuries from bicycle accidents, the government should concentrate more on educating people about bicycle safety and less on encouraging or requiring bicyclists to wear helmets.”

The following appeared in a health newsletter.

“A ten-year nationwide study of the effectiveness of wearing a helmet while bicycling indicates that ten years ago, approximately 35 percent of all bicyclists reported wearing helmets, whereas today that number is nearly 80 percent. Another study, however, suggests that during the same ten-year period, the number of bicycle-related accidents has increased 200 percent. These results demonstrate that bicyclists feel safer because they are wearing helmets, and they take more risks as a result. Thus, to reduce the number of serious injuries from bicycle accidents, the government should concentrate more on educating people about bicycle safety and less on encouraging or requiring bicyclists to wear helmets.”

Write a response in which you examine the stated and/or unstated assumptions of the argument. Be sure to explain how the argument depends on these assumptions and what the implications are for the argument if the assumptions prove unwarranted.

The argument suggests two conclusions about the bicycle helmet law. First, more bicyclists are wearing helmets because of the law, and second, helmets protect bicyclists from more serious injuries. Without more information, it is not possible to reach any firm conclusions. What evidence is there to support the first conclusion? If helmets were worn only because they were required by law, then it is reasonable to expect the percentage of bicyclists wearing helmets to decline once the law is repealed. Neither study discusses the percentage of bicyclists wearing helmets when riding outside of a protected bike lane. If the number of cyclists without helmets continues to increase without a change in the law, then it is likely that helmets will continue to be worn, regardless of law.

The second conclusion, however, is unsupported by the evidence offered. The decrease in the number of bicycle-related accidents could result from an increase in the amount of education bicyclists receive. A bicycle helmet is designed to keep bicyclists’ heads and faces from injury. If the helmet kept heads and faces intact, then the accident rate among helmeted bicyclists would have remained the same. If the helmet prevented the cyclist from sustaining a head or facial injury, then the bicyclist’s rate of accident injury would have decreased. The studies cited do not establish whether bicycle helmets are effective in preventing bicycle accidents. A helmet that saves a bicyclist from injury could motivate the bicyclist to ride more aggressively, increasing the rate of bicycle accidents. The lack of evidence supporting the second conclusion demonstrates that the studies do not provide a sufficient basis for a conclusion about the effectiveness of bicycle helmets.

The argument would benefit from additional evidence. If helmet laws reduce the number of bicycle-related accidents, then it is reasonable to conclude that bicycle helmets are effective. If, however, helmets actually contribute to a surge of bicycle accidents, then the argument against helmet laws may be strengthened. Without additional research, it is not possible to reach a firm conclusion about the effectiveness of the helmet law.