In Kennedy v. Magone, the Supreme Court of the United States ruled on a dispute involving customs duties. The plaintiff, Kennedy, imported iron ore into New York from Canada and was charged with a duty under an 1890 tariff act that imposed taxes on ores according to their metallic content. However, he argued that his imports should have been exempted from this tax because they were intended for use in making pig-iron and not as ore per se; thus falling under another provision of the same act which allowed such exemptions. The court disagreed with Kennedy's interpretation of the law stating that it would lead to absurd results if importers could avoid paying duties simply by declaring different uses for their goods after importation but before sale or consumption within U.S borders. Therefore, it upheld lower courts' decisions requiring him to pay full duties on his imports regardless of their intended use.

In the dissenting opinion for Kennedy v. Magone, Justice Brewer argued that the majority's interpretation of the Tariff Act was incorrect. He believed that Congress intended to tax imported merchandise stored in bonded warehouses at rates set by laws existing when goods were withdrawn, not when they entered. The majority’s decision would lead to a significant loss of revenue for the government as importers could store their goods indefinitely until tariff rates decreased before withdrawing them from warehouses. This would also give an unfair advantage to foreign manufacturers over domestic ones because they could manipulate timing and storage of their products based on fluctuating tariffs while domestic producers had no such luxury with taxes imposed upon them remaining constant regardless of market conditions or legislative changes.