This case dealt with the extent of state authority over the activities of non-Indians engaged in commerce on an Indian reservation. The State of Arizona sought to apply its motor carrier license and use fuel taxes to petitioner Pinetop Logging Co, an enterprise consisting of two non-Indian corporations. Pinetop operated solely on the Fort Apache Reservation, felling tribal timber and transporting it to the tribal organization’s sawmill. Pinetop and petitioner White Mountain Apache Tribe contended that the taxes were preempted by federal law or, alternatively, that they represented an unlawful infringement on tribal self-government. The Supreme Court held that the taxes were preempted by federal law. The Court was of the view that where, as here, a State asserted authority over the conduct of non-Indians engaging in activity on the reservation, a particularized inquiry had to be made into the nature of the state, federal, and tribal interests at stake. It decided that imposition of the taxes in question would undermine the federal policy of assuring that the profits from timber sales would inure to the Tribe’s benefit; would also undermine the Secretary of the Interior’s ability to make a wide range of determinations concerning the setting of fees with respect to the harvesting and sale of tribal timber; and would adversely affect the Tribe’s ability to comply with the sustained-yield management policies imposed by federal law.