The Supreme Court held that federal law does not preempt tribal authority unless Congress clearly expressed its intent to do so.

Crow Dog, a Brule Sioux, was convicted and sentenced to death in a Dakota territorial court for the murder of another Sioux. Under tribal law, Crow Dog would not have received a sentence of death but would have been required to support the victim’s family. He sought a writ of habeas corpus, contending that the federal government had no criminal jurisdiction over disputes among Native Americans in Indian territory. The U.S. government asserted that the Treaty of 1868 implicitly provided for federal jurisdiction over criminal prosecutions.[case]Crow Dog, Ex parte[Crow Dog, Ex parte]Native American sovereignty;Crow Dog, Ex parte[Crow Dog, Ex parte]

By a 9-0 vote, the Supreme Court ruled in favor of Crow Dog’s claim. In his opinion, Justice Stanley MatthewsMatthews, Stanley;Crow Dog, Ex parte[Crow Dog, Ex parte] wrote that although Congress possessed the constitutional authority to determine the scope of Indian self-government, it had not clearly expressed its intent to limit tribal authority in Dakota territory. Unless the legislation was explicit, the Indian tribes retained exclusive jurisdiction over Indian affairs on the reservations. Reacting to the decision, Congress in 1885 passed the Major Crimes Act,Major Crimes Act which provided federal jurisdiction over seven felonies committed on Indian lands.

The Crow Dog precedent, which remains good law, requires that treaties and statutes are normally interpreted in favor of retained Indian sovereignty and treaty rights. This principle is especially important in regard to nineteenth century documents that tend to contain many ambiguities. In areas such as the retained rights to hunt and fish, for example, the Crow Dog decision often helped Native American lawyers prevail in court.[case]Crow Dog, Ex parte[Crow Dog, Ex parte]

Indian Bill of Rights

Lone Wolf v. Hitchcock

Native American sovereignty

Native American treaties