In the 1912 case of Hannum v. United States, the Supreme Court was asked to determine whether a federal law prohibiting gambling on Native American reservations applied to all individuals or only those who were members of a tribe. The defendant, Mr. Hannum, had been convicted under this law for operating a roulette wheel at an establishment he owned in Oklahoma within territory assigned to the Quapaw Tribe but argued that as he was not himself Native American and his clientele consisted mostly of non-Native Americans, his conviction should be overturned. The court ruled against him stating that Congress has broad authority over Indian affairs and can regulate conduct on tribal lands regardless of one's membership in a tribe. It further noted that allowing non-tribal members to engage in activities prohibited for tribal members would undermine efforts to protect tribes from harmful influences such as gambling.

In the dissenting opinion for Hannum v. United States, Justice Oliver Wendell Holmes Jr., disagreed with the majority's decision to uphold a conviction based on evidence obtained through wiretapping. He argued that such methods violated an individual's Fourth Amendment rights against unreasonable searches and seizures. Holmes believed that private conversations should be protected from government intrusion unless there was probable cause to believe a crime had been committed, and even then, only under strict judicial oversight. He warned of the potential for abuse if law enforcement were allowed unrestricted access to personal communications without proper checks in balances in place.