Federal Power Commission v. Florida Power & Light Co.

Background

A large Florida electric company, serving nearly one million customers, was accused of transmitting power that reached other States through its connections with a nearby utility and the broader national grid. The Federal Power Commission (FPC) used two technical approaches to decide the company was subject to federal oversight: an "electromagnetic unity" theory and a tracing or "commingled" study of flows at a shared connection point called the Turner bus. A federal appeals court set aside the FPC’s finding, and the case reached the Supreme Court.

Reasoning

The Court considered whether the FPC had enough factual support to say the company’s electricity left Florida. The majority relied on the FPC’s commingling analysis and expert testimony, saying courts should defer to an agency’s technical findings when supported by substantial evidence. The Court did not fully endorse the electromagnetic-unity theory but held the tracing studies plus expert opinion were enough to show some of the company’s power reached out of State and therefore fell under the Act.

Real world impact

The ruling reinstated the FPC order that the utility is subject to federal regulation and sent the case back for enforcement of that order. Because many private utilities are tied into regional grids, the decision may expand when federal oversight applies versus state control. The Court emphasized that small or hard-to-measure transfers can still establish federal jurisdiction when supported by expert evidence.

Dissents or concurrances

A dissenting Justice warned that the commingling method is speculative, could federalize nearly all interconnected utilities, and might upset Congress’s intent to leave many matters to state regulation.