Here (the remainder of the briefs are on the Yellen v. Chehalis backgrounds materials page):
Here are the merits briefs:
Amicus Briefs Supporting Petitioners:
Amicus Briefs Supporting Respondents:
Cert Stage Briefs
D.C. Circuit materials:
District Court materials:
Here is the petition in Mnuchin v. Confederated Tribes of the Chehalis Reservation:
Whether Alaska Native regional and village corporations established pursuant to the Alaska Native Claims Settlement Act are “Indian Tribe[s]” for purposes of the CARES Act, 42 U.S.C. 801(g)(1).
The Alaska Native Corps petition is here.
Lower court materials here.