In Thomas Moore, Executor of Richard Eels v. The People of the State of Illinois, the Supreme Court was asked to decide whether a state could tax property that had been inherited from another state. At issue was an inheritance tax imposed by Illinois on certain real estate located in Indiana and owned by Richard Eels at his death. The executor argued that such taxation violated the Constitution's Privileges and Immunities Clause because it interfered with interstate commerce. In a 5-4 decision, the court held that states have no authority to impose taxes on property located outside their borders and thus overturned the lower court ruling upholding Illinois' imposition of its inheritance tax on this out-of-state property. This case established important precedent for determining when states may or may not interfere with interstate commerce through taxation measures.

In Thomas Moore, Executor of Richard Eels v. The People of the State of Illinois, Justice Curtis delivered a dissenting opinion in which he argued that the plaintiff's right to receive compensation for his services as an executor had been violated by the state. He noted that under English common law and American statutes, executors were entitled to reasonable fees for their work and that this was not only a matter of justice but also necessary to encourage people to take on such roles. Furthermore, he argued that since there was no dispute over whether or not the plaintiff had performed his duties properly or diligently enough, it would be unjust for him not to receive any payment at all. In conclusion, Justice Curtis believed that denying compensation in this case would set a dangerous precedent and could lead other states down a slippery slope where they too might deny rightful payments due from executors who have fulfilled their obligations faithfully.