In Evanston v. Gunn, the Supreme Court of the United States was asked to decide whether a city could impose a tax on the sale of goods within its borders. The city of Evanston, Illinois had imposed a tax on the sale of goods within its borders, and the defendant, Gunn, had challenged the tax as unconstitutional. The Supreme Court held that the tax was constitutional. The Court reasoned that the power to tax was an inherent power of the state, and that the state could impose taxes on the sale of goods within its borders. The Court also noted that the tax was not discriminatory, as it applied equally to all goods sold within the city. The Court also held that the tax was not a violation of the Commerce Clause, as it did not interfere with interstate commerce. The Court noted that the tax was imposed on the sale of goods within the city, and not on the sale of goods between states. Finally, the Court held that the tax was not a violation of the Due Process Clause, as it was not arbitrary or oppressive. The Court noted that the tax was imposed on all goods sold within the city, and that it was not excessive or unreasonable. In conclusion, the Supreme Court held that the tax imposed by the city of Evanston, Illinois was constitutional. The Court reasoned that the power to tax was an inherent power of the state, and that the tax was not discriminatory, a violation of the Commerce Clause, or a violation of the Due Process Clause.

Justice Field delivered the dissenting opinion in Evanston v. Gunn, arguing that the Court should not have granted a writ of error to review the decision of an Illinois state court. He argued that there was no federal question involved and thus it was inappropriate for a federal court to intervene in this case. The dispute between Evanston and Gunn concerned whether or not certain property belonged to one party or another under Illinois law; as such, Justice Field believed it should be decided by an Illinois state court rather than by a federal court. Furthermore, he noted that even if there had been some sort of constitutional issue at stake, it would still have been improper for the Supreme Court to grant certiorari because none of those issues were raised before either lower courts nor did they appear on appeal from any other jurisdiction's judgment. In conclusion, Justice Field maintained his position that this case should never have come before the Supreme Court since its resolution depended solely upon questions concerning local laws which could only be answered by an appropriate state tribunal with expertise in such matters.