James Clark McReynolds,
Hendrick v. Maryland — Opinion of the Court
“ In the absence of national legislation covering the subject, a state may rightfully prescribe uniform regulations necessary for public safety and order in respect to the operation upon its highways of all motor vehicles,-those moving in interstate commerce as well as others. And to this end it may require the registration of such vehicles and the licensing of their drivers, charging therefor reasonable fees graduated according to the horse-power of the engines,-a practical measure of size, speed, and difficulty of control. ”
