Kelly v. Hedden is a United States Supreme Court case that was decided in 1887. The case involved a dispute between a fruit importer and the United States government over the importation of tomatoes. The importer, John Kelly, argued that tomatoes should be classified as vegetables for the purpose of taxation, while the government argued that tomatoes should be classified as fruit. The Supreme Court ultimately sided with the government, ruling that tomatoes should be classified as fruit for the purpose of taxation. The Court reasoned that the common understanding of the word "fruit" included tomatoes, and that the government had the right to impose taxes on imported fruits. The Court also noted that the classification of tomatoes as fruit was consistent with the common understanding of the word "fruit" and the purpose of the tariff laws. The decision in Kelly v. Hedden established the precedent that the government has the right to classify items for the purpose of taxation, and that the classification must be consistent with the common understanding of the item in question. This precedent has been used in numerous cases since then, and is still relevant today.

Justice Field delivered the dissenting opinion in Kelly v. Hedden, arguing that Congress had no authority to impose a tax on tomatoes as vegetables under the Tariff Act of 1883. He argued that while Congress has broad powers over taxation, it cannot use those powers to redefine words and terms used in its own laws. In this case, he argued that tomatoes are not "vegetables" within the meaning of the statute because they are botanically classified as fruits; thus, imposing a tax on them was beyond Congress' power and unconstitutional. Furthermore, Justice Field noted that if such an interpretation were allowed to stand then any other word or phrase could be redefined by Congress at will which would lead to chaos and confusion with respect to federal law enforcement efforts.