Do you prefer to pay income taxes or sales taxes? Missouri voters will get to choose in a unique ballot question later this year. A proposed constitutional amendment will give people the option of gradually eliminating the individual income tax in exchange for the possibility that lawmakers could expand the sales tax to more services. This marks the first time a U.S. state legislature has asked voters to make such a choice. Kentucky, Mississippi and Oklahoma also recently passed laws that could phase out their income tax if revenue benchmarks are met. But those didn't go to voters.