The Bureau of Indian Affairs (BIA) was required by the Indian Reorganization Act of 1934, 25 U.S.C. § 461, to grant a preference in hiring to American Indians. In 1972, the BIA adopted a policy that also granted a preference to American Indians in promotions. A class of non-Indian BIA employees (plaintiffs) sued the secretary of the interior, the commissioner of Indian affairs, and various BIA directors (defendants), alleging that the Equal Employment Opportunity Act of 1972, 42 U.S.C. § 2000e, had repealed the provision of the Indian Reorganization Act that authorized a preference for Indians. The district court ruled that the Indian-preference provision had been implicitly repealed and permanently enjoined the BIA from implementing any policy that would grant a preference to Indians. The defendants appealed to the United States Supreme Court.