The Supreme Court of the United States held that "self-determination" contracts between the Federal Government and Native American tribes are as binding on the Federal Government as any other contractor agreement.
Cherokee Nation of Oklahoma v. Leavitt, 543 U.S. 631 (2005).
Contracts Formed under the Indian Self-Determination and Education Assistance Act Are as Binding as Any Other Government Agreements with a Contractor: Cherokee Nation of Oklahoma v. Leavitt,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol44/iss2/11