Proper gear and a helmet do not guarantee you will survive a crash. Wearing a seatbelt does not guarantee you survive a crash. There are no guarantees in life. But seatbelts as well as proper gear and a helmet significantly increase your chances surviving a serious crash. There is no argument that can successfully be made against that fact. It has been statistically proven over and over again. Even the organizations that argue against mandatory helmet laws generally do not dispute that fact, but instead base their arguments on personal freedom, choice and acceptance of risk.
I agree with that argument. We have too much government and too many laws as it is. If someone wants to put their own life at risk, they should have that right. I don’t think a helmet law should be imposed on riders over the age of 21. Let people make their own choices. It’s better for society as a whole in the long run.
That being said, I can say from personal knowledge that helmets do save lives. My brother used to ride, and hit a tree one night. He fractured his skull, collarbone, wrist, several ribs and his leg. He spent a week in intensive care and a total of 49 days in Strong Memorial Hospital. I clearly remember the Dr saying that without that helmet (which actually cracked in the crash) there was zero chance he would have survived. I always wear full gear when I ride, and always will.