Contemporary federal court decisions, statutes, and presidential statements often provide strong support for tribal self-government. According to U.S. judicial doctrine, for example, tribal legal regimes survive as manifestations of indigenous sovereign powers, rather than as creations of federal law. In keeping with this notion, the Bill of Rights of the Constitution does not apply to actions of tribal governments because the first ten amendments to the Constitution bind only the federal government and its agencies, not independent sovereigns such as Indian nations. Furthermore, a criminal defendant can be convicted for the same crime in federal and tribal court without being placed in double jeopardy, because the protection against double jeopardy in the U.S. Constitution does not apply to situations where a person is convicted for the same crime by two separate sovereigns.
If Native American tribes are not federal agencies, however, neither are they mere voluntary associations, like private clubs, whose powers are limited to admitting and excluding members. Instead, they are governing bodies with the power to direct and coerce individuals engaged in activities within their territory, more like cities and states. The U.S. Supreme Court has affirmed, for example, that tribes may impose taxes on activities by Native Americans and non-Native Americans alike in Indian Country.
The Supreme Court has also tried to place some limits on tribes' sovereign powers, particularly where non-Native Americans or Native Americans who are members of other tribes are involved. Finding that the incorporation of tribes into the United States necessarily reduced the scope of tribal powers, the Supreme Court has held that tribal sovereignty does not include the power to engage in foreign relations, to wage war, to alienate (transfer an ownership interest in) tribal land, or to impose criminal punishments on non-members of the tribe. The Court has also restricted the power of tribes to regulate the activities of non-members on land that is owned by non-members but is located within the reservation, at least if those activities have no substantial bearing on the health or well-being of tribal members. These determinations by the Supreme Court are judge-made law, drawing on the history and practices of federal Native American law, but not directly tied to language of the U.S. Constitution or specific federal statutes. Consequently, the Court ordinarily acknowledges in its decisions limiting tribal powers that Congress can restore those powers by enacting legislation that offers a contrary interpretation of the history and practice.
Law Library - American Law and Legal InformationGreat American Court CasesNative Americans - Tribal Governance, Monitoring Government Interference, Support For Tribal Sovereignty, Treaty-making Before 1871