In the case of Federal Power Commission v. Metropolitan Edison Co., the U.S Supreme Court ruled in 1937 that the Federal Power Commission (FPC) had jurisdiction over wholesale rates for electricity sold by public utilities to other utility companies, even if those sales were made within a single state. The court held that such transactions constituted interstate commerce and thus fell under federal regulation. This decision was significant because it expanded federal power over energy markets, which previously had been largely regulated at the state level. It also clarified how far-reaching Congress's powers could be when regulating interstate commerce in relation to electric utilities.

The dissenting opinion in the case of Federal Power Commission v. Metropolitan Edison Co. et al., argued that the majority's interpretation of the Federal Water Power Act was too broad and overreached its intended scope. The dissent contended that Congress did not intend for the act to apply to all bodies of water, but rather only those which were navigable or directly affected interstate commerce. They believed this because historically, regulation of local utilities had been a matter left to individual states, not federal jurisdiction. Therefore, they disagreed with the majority's decision that allowed for federal intervention into what they saw as state matters based on an overly expansive reading of congressional intent.