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25 U.S. Code § 5374 - Effect of circulars, policies, manuals, guidance, and rules

Unless expressly agreed to by a participating Indian Tribe in a compact or funding agreement, the participating Indian Tribe shall not be subject to any agency circular, policy, manual, guidance, or rule adopted by the Department, except for—
the eligibility provisions of section 5324(g) of this title; and
regulations promulgated pursuant to section 5373 of this title.