Syllabus
Held: The 1868 treaty establishing the Navajo Reservation reserved necessary water to accomplish the purpose of the Navajo Reservation but did not require the United States to take affirmative steps to secure water for the Tribe. Pp. 6–13.
(a) The Tribe asserts a breach-of-trust claim based on its view that the 1868 treaty imposed a duty on the United States to take affirmative steps to secure water for the Navajos. To maintain such a claim here, the Tribe must establish, among other things, that the text of a treaty, statute, or regulation imposed certain duties on the United States. See United States v. Jicarilla Apache Nation, 564 U. S. 162, 173–174, 177–178. The Federal Government owes judicially enforceable duties to a tribe “only to the extent it expressly accepts those responsibilities.” Id., at 177. Whether the Government has expressly accepted such obligations “must train on specific rights-creating or duty-imposing” language in a treaty, statute, or regulation. United States v. Navajo Nation, 537 U. S. 488, 506.
Here, while the 1868 treaty “set apart” a reservation for the “use and occupation of the Navajo tribe,” 15 Stat. 668, it contains no language imposing a duty on the United States to take affirmative steps to secure water for the Tribe. See Navajo Nation, 537 U. S., at 506. Notably, the 1868 treaty did impose a number of specific duties on the United States, but the treaty said nothing about any affirmative duty for the United States to secure water. As this Court has stated, “Indian treaties cannot be rewritten or expanded beyond their clear terms.” Choctaw Nation v. United States, 318 U. S. 423, 432.
To be sure, this Court’s precedents have stated that the United States maintains a general trust relationship with Indian tribes, including the Navajos. Jicarilla, 564 U. S., at 176. But unless Congress has created a conventional trust relationship with a tribe as to a particular trust asset, this Court will not “apply common-law trust principles” to infer duties not found in the text of a treaty, statute, or regulation. Id., at 178. Here, nothing in the 1868 treaty establishes a conventional trust relationship with respect to water. And it is unsurprising that a treaty enacted in 1868 did not provide for all of the Navajos’ current water needs 155 years later. Under the Constitution, Congress and the President have the responsibility to update federal law as they see fit in light of the competing contemporary needs for water.
