Comanche Nation of Oklahoma v. Zinke

In June 2014, Chickasaw Nation asked the United States Department of the Interior to take land near Terral, Oklahoma, into trust for Chickasaw Nation’s benefit so that Chickasaw Nation could use the land for a casino. The Terral land was located near a gaming facility operated by the Comanche Nation of Oklahoma (Comanche Nation) (plaintiff). The secretary of the interior (the secretary) (defendant) concluded that the Terral land could be taken into trust under the Indian Reorganization Act (IRA) because Chickasaw Nation no longer had a reservation in Oklahoma, and the land was within the boundaries of Chickasaw Nation’s former Oklahoma reservation. The secretary also determined that the land could be used for gaming under the Indian Gaming Regulatory Act (IGRA). The Bureau of Indian Affairs (BIA) conducted a detailed environmental assessment and issued a finding of no significant impact from the acquisition of the Terral land for gaming purposes. In 2017, Comanche Nation sued the secretary in federal court. Comanche Nation asserted that the secretary had improperly concluded that the Terral land could be taken into trust under the IRA because the secretary had not determined that Chickasaw Nation had exercised governmental jurisdiction over the land prior to the acquisition. Comanche Nation also asserted that the secretary had violated the National Environmental Policy Act (NEPA) by failing to sufficiently examine the environmental impact of Chickasaw Nation’s proposed casino. Comanche Nation sought injunctive relief preventing Chickasaw Nation from opening a casino on the Terral land, but the district court denied relief. Comanche Nation appealed.