Harshman v. Bates County was a United States Supreme Court case that dealt with the issue of taxation. The case involved a dispute between the plaintiff, Harshman, and the defendant, Bates County, over the taxation of certain lands owned by Harshman. Harshman argued that the taxation of his lands was unconstitutional, as it violated the Fourteenth Amendment's Equal Protection Clause. The Supreme Court ultimately sided with Harshman, ruling that the taxation of his lands was unconstitutional. The Court held that the taxation of Harshman's lands was unconstitutional because it was based on a classification that was not reasonable and did not bear a rational relationship to the purpose of taxation. The Court noted that the taxation of Harshman's lands was based on a classification that was not based on any reasonable basis, and that the taxation of his lands was not related to any legitimate purpose of taxation. The Court concluded that the taxation of Harshman's lands was unconstitutional, and that the defendant, Bates County, was liable for the taxes that had been collected from Harshman.

Justice Field delivered the dissenting opinion in Harshman v. Bates County, arguing that the majority’s decision was wrongfully based on a misinterpretation of Missouri state law. He argued that under Missouri law, when an individual purchases land from another party who does not have title to it, they are still able to acquire legal title if they pay for it and occupy it for five years without interruption or dispute from any other parties with superior claims. In this case, he noted that Harshman had done exactly this – paid his purchase price and occupied the property uninterruptedly since 1845 – yet was denied legal title by the court due to its interpretation of state law as requiring payment of taxes during those five years in order to obtain valid title. Justice Field disagreed with this interpretation and argued instead that paying taxes should be seen as merely one way among many possible ways for obtaining valid ownership rights over disputed lands; thus, he concluded that Harshman should have been granted full legal ownership rights over his purchased property despite failing to pay taxes during those five years.