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This Article is the first of a two-part investigation into the Indian law doctrine of reservation diminishment/disestablishment, examining Supreme Court decisions in this area in light of insights gathered from the collected papers of individual Justices archived at the Library of Congress and various university libraries. The Article first addresses Seymour v. Superintendent (1962) and Mattz v. Arnett (1973), observing that these first two diminishment/disestablishment cases are modern applications of basic, longstanding principles of Indian law which are highly protective of Indigenous people’s rights and tribal sovereignty. The Article then examines in detail DeCoteau v. District County Court, the anomalous 1975 decision in which the Supreme Court held that an 1889 land-sale agreement between the United States and the Sisseton-Wahpeton Dakota Indians, which Congress ratified in 1891, had abolished the boundaries of the Lake Traverse Reservation in South Dakota and North Dakota, a reservation that had been established as the Indians’ “permanent reservation” home in an 1867 treaty. The Article critiques DeCoteau in view of the historical context of the 1862 U.S.-Dakota War, an explosive conflict that resulted in the forced removal of the Dakota people from their reservation and aboriginal homelands in Minnesota and the abrogation of all U.S.-Dakota treaties, including treaty rights that guaranteed annual payments essential for the Indians’ subsistence and survival. The Article brings into view the full scope of the negotiations between the Sisseton- Wahpeton people and U.S. commissioners in 1889, demonstrating that the Dakota people never consented to any reduction or elimination of reservation boundaries when they agreed, under desperate circumstances, to sell to the United States the unallotted lands within the reservation. The Article further surveys additional evidence, unaddressed by the Supreme Court, regarding the 1891 Act’s legislative history, including numerous congressional debates and provisions of reports of the Senate and House of Representatives, as well as evidence from Executive Branch sources, which collectively show that the 1891 Act did not shrink or terminate the reservation. The Article posits that DeCoteau, which scholars recognize as having initiated a “magic language” mode of analysis in the reservation diminishment/disestablishment area, cannot be reconciled with fundamental principles of Indian law. Finally, the Article inspects and discusses documents from the archived papers of the Justices who took part in DeCoteau, unraveling clues that may help account for the Supreme Court’s aberrant decision.

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Indigenous Peoples' Journal of Law, Culture & Resistance





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Indian law, Reservation diminishment/disestablishment, Seymour v. Superintendent, Mattz v. Arnett, DeCoteau v. District County Court, Tribal sovereignty, Sisseton-Wahpeton Dakota Indians, Lake Traverse Reservation



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