Arizona v. Navajo Nation

What happened

After an 1849 treaty, the two sides were often at war, and the United States forcibly moved many Navajos from their homeland to the Bosque Redondo Reservation in New Mexico. In 1868 the two sides agreed to a second treaty. The United States "set apart" a large reservation "for the use and occupation of the Navajo tribe," on the Navajos' original homeland. The reservation today spans some 17 million acres, almost entirely in the Colorado River Basin.

Under Winters v. United States (1908), a reservation of land implicitly reserves the water needed for it. The Navajo Nation argued that federal efforts to help with its water needs did not satisfy the United States' trust obligations under the 1868 treaty. It sued to make the United States assess the Tribe's water needs, plan to secure the water, and possibly build pipelines, pumps, wells or other infrastructure. Arizona, Nevada and Colorado intervened against the Tribe, and the Ninth Circuit held the treaty imposed that duty.

The Supreme Court reversed, 5-4, in an opinion by Justice Kavanaugh. It said the treaty "reserved necessary water" for the reservation, but did not require affirmative steps. To bring such a claim, the Tribe must show a treaty, statute or regulation that imposed the duty, and the government owes enforceable duties only to the extent it expressly accepts them. Justice Gorsuch dissented, joined by three other justices.

The Winters right stands; the decision limits claims that the trust relationship requires the United States to build water infrastructure.

Good to know. The account of Bosque Redondo here is the majority's; the dissent describes the removal at greater length.

Summarized with AI assistance from 3 sources and checked against their words; not yet reviewed by historians or by the nations. Report an error