The U.S. Supreme Court case Morton, Secretary of the Interior v. Ruiz et ux., 1973 revolved around a dispute over federal benefits for Native Americans living off reservations. The Bureau of Indian Affairs (BIA) had been providing general assistance benefits to needy Indians both on and off reservations until it issued an internal memorandum limiting these benefits only to those residing on reservation lands or in "near-reservation" areas. This policy change was not published in the Federal Register nor subjected to public comment as required by law, leading Mr. Ruiz, who lived outside such designated areas but within original boundaries of a reservation, to sue when his application for aid was denied based on this unpublished rule. The Supreme Court ruled that BIA's failure to publish its new eligibility criteria violated the Administrative Procedure Act (APA), which mandates publication of substantive rules affecting individual rights and obligations before they can be enforced against individuals like Mr.Ruiz. The court also found that BIA’s interpretation excluding certain groups from receiving aid conflicted with Congress' intent behind relevant statutes - namely ensuring welfare needs are met among all impoverished Indians regardless their place of residence.

In the dissenting opinion for Morton v. Ruiz, Justice Rehnquist argued that the majority had overstepped its judicial role by imposing a requirement on administrative agencies to publish all substantive rules in the Federal Register. He contended that this was not mandated by any statute or constitutional provision and thus should be left to legislative discretion. Furthermore, he disagreed with the majority's interpretation of "Indian country" as including off-reservation trust lands, asserting it contradicted previous court rulings and congressional intent. He also criticized their decision to extend benefits under Bureau of Indian Affairs (BIA) programs to Indians living on such lands without clear statutory authorization from Congress. In his view, these decisions amounted to an unwarranted intrusion into executive branch functions and threatened separation of powers principles.