In the 1894 case of South Carolina v. Wesley, the U.S. Supreme Court ruled on a dispute involving state taxation and interstate commerce. The State of South Carolina had imposed a tax on every bale of cotton compressed within its borders for transportation or shipment to another state, which was challenged by Mr. Wesley who operated a cotton compressing business in Charleston, SC. The court held that this tax constituted an unconstitutional burden on interstate commerce as it directly taxed goods destined for exportation to other states before they began their final journey out of the exporting state (South Carolina). This decision reaffirmed previous rulings that states cannot impose taxes or duties that would interfere with free trade among them under the Commerce Clause of the Constitution. Therefore, while acknowledging states' rights to levy taxes for revenue purposes, such powers must not infringe upon federal jurisdiction over interstate commerce - reinforcing principles central to maintaining economic unity across all US States.

The dissenting opinion in the case of South Carolina v. Wesley argued that the majority's decision to uphold a state law imposing taxes on commercial activities conducted by non-residents was unconstitutional. The dissenters believed this violated the Privileges and Immunities Clause of Article IV, Section 2, which guarantees citizens in each state all privileges and immunities granted to citizens in other states. They contended that this clause should protect out-of-state businesses from discriminatory taxation practices imposed by individual states. Furthermore, they disagreed with the majority's interpretation of what constitutes a privilege or immunity under this clause, arguing for a broader definition that includes economic rights such as conducting business across state lines without facing undue burdens or discrimination.