Another point to consider in the helmet freedom of choice debate is litigation.
Let's say that a rider is out without a helmet. Through no fault of his own, a careless driver hits him and he suffers a serious head injury resulting in permanent disability. Guess what - the insurance company will argue before a jury that ample evidence of risk of serious injury while riding without a helmet exists. The rider choosing to ride without a helmet despite the evidence of enhanced safety, has contributed to the extent of his injury and disability. Therefore any damages awarded must be apportioned with the riders contribution considered. In other words, the rider wouldn't get the full amount of compensation he may have been awarded if he had a helmet on his head.
Interesting argument. However, the plaintiff's attorney would be able to argue an equally persuasive position that actions of the victim in no way mitigate the fault of the errant driver who recklessly hit and killed him. Even if the plaintiff lost that argument, it's not a justification for helmet laws. It just adds to the personal risk.
"Dancing, marshmallows?" Cute.
This discussion is about prevention, preventing you and I from paying for some one else's irresponsibility. If you'd rather pay for that in taxes and insurance premiums rather than have common sense regulation your vote not mine.
Well, the discussion often is about that, but it shouldn't be. This is a common "red herring" argument made by helmet law enthusiasts. I simply do not buy it. When you insure a vehicle - even a motorcycle - the vast majority of the premium pays for liability, and comp & collision for your own vehicle. The medical rider that covers your own injury is always a relatively low cost, non-mandatory coverage. As for the "other guy's policy" I really doubt whether liability costs for automobile polices are much effected by whether or not the state has a helmet law. Bob may be better able to address that.
If, OTOH, you were talking about the cost of medical insurance, the costs that drive those rates are so gigantic, and so massively inclusive of all that drives the cost of medical insurance, that excess risk from insuring someone living in a state with no helmet law is miniscule. Sure there may be SOME additional risk to the insurer, but I'm guessing that it would equate to less than 35 cents per year per policy (considering the amount of total medical insurance polices written statewide) - just to throw a figure out there. You mention more taxes... What tax would be effected by motorcycle injuries? I cannot think of any.
This argument about the lack of a helmet law driving up costs for everybody simply doesn't hold water. The cost to individual insureds is so miniscule that it is indeed negligible. And any regulation that infringes upon the personal rights of individual members of a society, to the benefit of no one else, could hardly be labeled as "common sense regulation". That's NOT what government should be about - at ANY level.
I hope my comments don't offend you. Be assured that I am not personally attacking you. I'm just trying to coat those "dancing marshmallows" with a little "Common Sense" reality (to use a 1776 analogy from Thomas Paine.)

Sorry for that... Bob's analogy of
"dancing around the fire, without cooking the marshmallows" was probably a better one. 