The Indian Nations on this Reservation come from the Assiniboine and Sioux tribes. Their constitution was completely rewritten and adopted in 1960. It remains one of the few modern tribal constitutions that still include provisions for general councils, the traditional tribal type of government. The official governing body of the Fort Peck Tribes is the Tribal Executive Board, composed of twelve voting members, plus a chairman, vice-chairman, secretary-accountant, and sergeant-at-arms. All members of the governing body, except the secretary-accountant are elected at large every two years by enrolled members of the tribes.

Fort Peck Assiniboine & Sioux Tribes
PO Box 1027 | 501 Medicine Bear Road 
Poplar, MT 59255

Fort Peck Tribal Court

The court exercises jurisdiction over all offences by an Indian committed within the boundaries of the Fort Peck Indian Reservation. It also has civil jurisdiction over actions where a party is an Indian, or a corporation or entity owned in whole or in substantial part by an Indian. The court is set out in four divisions: Criminal, Civil, Family, and Youth Court. There are 4 judges and three appellate judges. Admission to practice before the courts requires attorneys or lay advocates to successfully complete the qualifying bar examination. The courts are located at the following address:

Fort Peck Tribal Court
Box 1027
Poplar, MT  59255

Assiniboine & Sioux Reservation