"In the three years after Michigan repealed a mandatory motorcycle helmet law, deaths and head injuries among bikers rose sharply, according to a recent study. Deaths at the scene of the crash more than quadrupled, while deaths in the hospital tripled for motorcyclists. Head injuries have increased overall, and more of them are severe, the researchers report in the American Journal of Surgery...Among the accident victims brought to the hospital, the proportion of riders who had not been wearing a helmet rose four-fold, from 7 percent to 28 percent, the researchers found. About 10 percent of non-helmeted riders brought to the hospital died there, compared to 3 percent of those who had been wearing helmets. Among riders who died at the crash scene, the proportion not wearing helmets rose from 14 percent before the law was repealed to 68 percent afterward."
One more thing deregulated, and the costs are apparent. It isn't just the biker who suffers--they have families, friends, people they work for or with, and so forth. Then there are the medical and rehab bills for people with brain injuries.