25 U.S.C. § 81: Contracts and agreements with Indian tribes

The term “Indian lands” means lands the title to which is held by the United States in trust for an Indian tribe or lands the title to which is held by an Indian tribe subject to a restriction by the United States against alienation. The term “Indian tribe” has the meaning given that term in section 5304(e) of this title . The term “Secretary” means the Secretary of the Interior. No agreement or contract with an Indian tribe that encumbers Indian lands for a period of 7 or more years shall be valid unless that agreement or contract bears the approval of the Secretary of the Interior or a designee of the Secretary. Subsection (b) shall not apply to any agreement or contract that the Secretary (or a designee of the Secretary) determines is not covered under that subsection. violates Federal law; or provides for remedies in the case of a breach of the agreement or contract; references a tribal code, ordinance, or ruling of a court of competent jurisdiction that discloses the right of the Indian tribe to assert sovereign immunity as a defense in an action brought against the Indian tribe; or includes an express waiver of the right of the Indian tribe to assert sovereign immunity as a defense in an action brought against the Indian tribe (including a waiver that limits the nature of relief that may be provided or the jurisdiction of a court with respect to such an action). Not later than 180 days after March 14, 2000 , the Secretary shall issue regulations for identifying types of agreements or contracts that are not covered under subsection (b). require the Secretary to approve a contract for legal services by an attorney; amend or repeal the authority of the National Indian Gaming Commission under the Indian Gaming Regulatory Act ( 25 U.S.C. 2701 et seq.); or alter or amend any ordinance, resolution, or charter of an Indian tribe that requires approval by the Secretary of any action by that Indian tribe.