Opinion of the Court
Treaty analysis begins with the text, and treaty terms are construed as “ ‘they would naturally be understood by the Indians.’ ” Fishing Vessel Assn., 443 U. S., at 676. Here it is clear that the Crow Tribe would have understood the word “unoccupied” to denote an area free of residence or settlement by non-Indians.
That interpretation follows first and foremost from several cues in the treaty’s text. For example, Article IV of the 1868 Treaty made the hunting right contingent on peace “among the whites and Indians on the borders of the hunting districts,” thus contrasting the unoccupied hunting districts with areas of white settlement. 15 Stat. 650. The treaty elsewhere used the word “occupation” to refer to the Tribe’s residence inside the reservation boundaries, and referred to the Tribe members as “settlers” on the new reservation. Arts. II, VI, id., at 650–651. The treaty also juxtaposed occupation and settlement by stating that the Tribe was to make “no permanent settlement” other than on the new reservation, but could hunt on the “unoccupied lands” of the United States. Art. IV, id., at 650. Contemporaneous definitions further support a link between occupation and settlement. See W. Anderson, A Diction
It can be “appropriate in special circumstances” for a court to address a preclusion argument sua sponte. Arizona v. California, 530 U. S. 392, 412 (2000). But because the Wyoming District Court “did not address” this contention, “we decline to address it here.” County of Los Angeles v. Mendez, 581 U. S. ___, ___, n. (2017) (slip op., at 8, n.); see Cutter v. Wilkinson, 544 U. S. 709, 718, n. 7 (2005); Archer v. Warner, 538 U. S. 314, 322–323 (2003). Resolution of this question would require factintensive analyses of whether this issue was fully and fairly litigated in Repsis or was forfeited in this litigation, among other matters. These gateway issues should be decided before this Court addresses them, especially given that even the dissent acknowledges that one of the preclusion issues raised by the parties is important and undecided, post, at 14, and some of the parties’ other arguments are equally weighty. Unlike the dissent, we do not address these issues in the first instance.
