Helmet laws and organ donors

Would it be repugnant to have a state helmet/donor law that said you are free to ride a motorcycle without wearing a helmet, but when you do so you assert that you wish to be an organ donor in the event of a fatal accident?

Here's a paper from 2011 that suggests such a law might have some effect, since apparently helmet laws reduce organ donations.

Donorcycles: Motorcycle Helmet Laws and the Supply of Organ Donors

Stacy Dickert-Conlin, Todd Elder (telder@msu.edu) and Brian Moore

Journal of Law and Economics, 2011, vol. 54, issue 4, pages 907 - 935

Abstract: Traffic safety mandates are typically designed to reduce the harmful externalities of risky behaviors. We consider whether motorcycle helmet laws also reduce a beneficial externality by decreasing the supply of viable organ donors. Our central estimates show that organ donations resulting from fatal motor vehicle accidents increase by 10 percent when states repeal helmet laws. Two features of this association suggest that it is causal: first, nearly all of it is concentrated among men, who account for over 90 percent of all motorcyclist deaths, and second, helmet laws are unrelated to the supply of donors who die in circumstances other than motor vehicle accidents. The estimates imply that every death of a helmetless motorcyclist prevents or delays as many as .33 death among individuals on organ transplant waiting lists.

Here's a related news story that came up when I searched:
Economist studies link between helmet-free bikers, organ donors