In the United States v. Chidester case of 1890, the Supreme Court ruled on a dispute involving mail fraud. The defendant, Mr. Chidester, was accused of using the U.S Postal Service to defraud individuals by sending them deceptive letters and advertisements about his business operations in mining stocks. He argued that he could not be prosecuted under federal law because his actions did not directly harm or interfere with postal service operations; rather they were private transactions between him and other parties. The court disagreed with this argument stating that Congress had broad authority to regulate interstate commerce which included mail services as well as protect citizens from fraudulent schemes conducted through these services. Therefore, even though Mr.Chidester's activities didn't physically obstruct or damage postal service infrastructure or personnel, it still constituted an abuse of a federally regulated system for illegal purposes. This ruling set a precedent for future cases involving mail fraud by clarifying that any misuse of the postal system for fraudulent activities can be subject to federal prosecution regardless if there is direct harm done to the operation of said system.

In the dissenting opinion for United States v. Chidester, it was argued that the defendant's actions did not constitute a violation of federal law because they were carried out in Indian Territory, which at the time was not considered part of U.S jurisdiction. The dissenting justices contended that Congress had no authority to enforce laws within this territory as it was under tribal sovereignty and thus outside their purview. They believed that any criminal acts committed there should be dealt with by local tribal authorities or through diplomatic channels rather than being prosecuted under U.S law. This interpretation held firm on respecting Native American self-governance and limiting Congressional overreach into territories where its power may not extend constitutionally.