In the case of Udall, Secretary of the Interior v. Federal Power Commission et al., 1966, the Supreme Court was asked to determine whether or not a power company could be granted a license by the Federal Power Commission (FPC) for construction on public lands without approval from the Secretary of Interior. The FPC had issued licenses to two companies for hydroelectric projects in national forests and recreation areas managed by other agencies within Department of Interior. However, these were done without obtaining consent from Udall as required under Section 4(e) of Federal Power Act which mandates that no such license affecting reservations shall be issued until department head responsible has agreed to it. The court ruled in favor of Udall stating that his authority over land management cannot be bypassed even if it impedes development plans approved by another federal agency like FPC.

In the dissenting opinion for UDALL, SECRETARY OF THE INTERIOR v. FEDERAL POWER COMMISSION et al., 1966, it was argued that the Federal Power Commission (FPC) should have jurisdiction over power projects on Indian reservations. The dissenters believed that Congress intended to give the FPC authority over all navigable waters of the United States and public lands, including those within Indian reservations. They contended that there is no explicit exclusion of Indian reservation lands in any legislation related to this matter and thus saw no reason why these lands should be treated differently from other federal properties under similar circumstances. Furthermore, they expressed concern about potential conflicts between tribal interests and national energy needs if tribes were given exclusive control over their resources without oversight or regulation by a federal agency like the FPC.