25 USC 1301 - Definitions
For purposes of this subchapter, the term
(1) Indian tribe means any tribe, band, or other group of Indians subject to the jurisdiction of the United States and recognized as possessing powers of self-government;
(2) powers of self-government means and includes all governmental powers possessed by an Indian tribe, executive, legislative, and judicial, and all offices, bodies, and tribunals by and through which they are executed, including courts of Indian offenses; and means the inherent power of Indian tribes, hereby recognized and affirmed, to exercise criminal jurisdiction over all Indians;
(3) Indian court means any Indian tribal court or court of Indian offense; and