In the case of Pleasants v. Greenhow, Treasurer, the Supreme Court of the United States was asked to decide whether a state could tax the income of a federal officer. The case arose when the Treasurer of Virginia attempted to collect a tax on the salary of a federal officer, William Pleasants. Pleasants argued that the state of Virginia had no authority to tax his salary, as it was a federal office. The Supreme Court held that the state of Virginia did not have the authority to tax the salary of a federal officer. The Court reasoned that the federal government had exclusive authority to tax the income of its officers, and that the state of Virginia could not interfere with this authority. The Court also noted that the federal government had the power to protect its officers from state taxation, and that the state of Virginia could not interfere with this power. The Court's decision in Pleasants v. Greenhow, Treasurer, established that the federal government has exclusive authority to tax the income of its officers, and that the states cannot interfere with this authority. This decision has been cited in numerous cases since, and has been used to protect the rights of federal officers from state taxation.

In the case of Pleasants v. Greenhow, Treasurer, the Supreme Court was tasked with determining whether a Virginia statute that authorized Confederate bonds to be issued and sold for taxes due in 1861 could be enforced against citizens who had not purchased them. The majority opinion held that since these bonds were issued by an unrecognized government during wartime, they did not constitute valid debt and thus could not be collected from those who had failed to purchase them. However, Justice Field dissented on this point arguing that although the Confederacy was no longer recognized as a legitimate government after its defeat in 1865, it still existed at the time when these bonds were issued and therefore should have been considered valid debt under state law. He further argued that even if it is assumed that these bonds are invalidated by their association with an unrecognized government then all other debts incurred during wartime would also become unenforceable which he believed would lead to great injustice and confusion among creditors.