Lake Traverse Reservation (Sisseton-Wahpeton) and DeCoteau v. District County Court (1975)

What happened

The United States made a treaty in 1867 with the Sisseton and Wahpeton bands of Sioux. As the Supreme Court describes it, the treaty gave them a permanent reservation at Lake Traverse, about 918,000 acres, with tribal self-government under federal supervision.

In 1889, after Congress passed the 1887 General Allotment Act, the tribe signed an agreement to sell all its unallotted land. The Court says the tribe agreed to "cede, sell, relinquish, and convey" its claim to that land for $2.50 per acre, and each member was to receive a 160-acre allotment. Congress ratified the agreement in the Act of 1891 and opened the ceded land to settlement under the homestead and townsite laws. So this change came through a negotiated agreement that Congress then enacted, not through a sudden unilateral act.

In DeCoteau v. District County Court (1975), the Court ruled 6-3 that the 1891 Act terminated the reservation. South Dakota courts therefore have civil and criminal jurisdiction over conduct on non-Indian, unallotted land inside the 1867 boundaries. Justice Douglas, with Justices Brennan and Marshall, dissented. The Court noted that about 3,000 tribal members and 30,000 non-Indians lived within the 1867 boundaries. In Solem v. Bartlett (1984) it later said that "Diminishment, moreover, will not be lightly inferred," and DeCoteau is a case where it found clear intent. This is an adjudicated loss of reservation status, not a finding that a treaty was broken.

Summarized with AI assistance from 2 sources and checked against their words; not yet reviewed by historians or by the nations. Report an error