In the case of Johnson Oil Refining Co. v. Oklahoma ex rel. Mitchell, County Attorney of Pawnee County et al., 1933, the U.S Supreme Court ruled in favor of Johnson Oil Refining Company (Johnson). The State of Oklahoma had attempted to impose a tax on gasoline produced by Johnson and transported out-of-state for sale. However, the court found that this violated interstate commerce laws as it was essentially an attempt to regulate and tax goods moving across state lines - something only federal law can do under the Commerce Clause in Article I Section 8 of the Constitution. Therefore, it was decided that states cannot levy taxes on products intended for export or interstate commerce before they have begun their journey out-of-state.

In the dissenting opinion for Johnson Oil Refining Co. v. Oklahoma, it was argued that the majority's decision to uphold an Oklahoma law prohibiting out-of-state oil companies from selling gasoline in the state unless they also maintained a refinery there violated principles of interstate commerce and equal protection under the Constitution. The dissenters contended that this law unfairly discriminated against out-of-state businesses by imposing undue burdens on their ability to compete in local markets, thereby violating their constitutional rights to engage freely in interstate trade. They further asserted that such discriminatory laws were not only unconstitutional but also detrimental to national economic unity and prosperity as they fostered parochialism at the expense of broader commercial interests.