Minnesota constitution
Article XIV
Section 9

The legislature by law may tax motor vehicles using the public streets and highways on a more onerous basis than other personal property. Any such tax on motor vehicles shall be in lieu of all other taxes thereon, except wheelage taxes imposed by political subdivisions solely for highway purposes. The legislature may impose this tax on motor vehicles of companies paying taxes under the gross earnings system of taxation notwithstanding that earnings from the vehicles may be included in the earnings on which gross earnings taxes are computed. The proceeds of the tax shall be paid into the highway user tax distribution fund. The law may exempt from taxation any motor vehicle owned by a nonresident of the state properly licensed in another state and transiently or temporarily using the streets and highways of the state.