In the case of Clark's Ferry Bridge Co. v. Public Service Commission of Pennsylvania, 1933, the U.S Supreme Court was tasked with determining whether a state could regulate tolls on a privately-owned interstate bridge without violating federal law or infringing upon interstate commerce regulations. The court ruled in favor of the Public Service Commission of Pennsylvania, stating that states have authority to regulate private entities providing public services within their jurisdiction unless explicitly prohibited by Congress. This includes setting reasonable rates for such services even if they involve interstate commerce like bridges connecting two states. Therefore, it upheld Pennsylvania’s right to control and adjust toll charges on Clark's Ferry Bridge despite its status as an interstate facility.

In the dissenting opinion for Clark's Ferry Bridge Co. v. Public Service Commission of Pennsylvania, it was argued that the majority had overstepped its bounds in interpreting state law and disregarded precedent regarding interstate commerce regulation. The dissent contended that the bridge company was not engaged in interstate commerce simply because its structure spanned a river dividing two states; rather, it provided a local service subject to state regulation. They believed that this case should have been decided based on whether or not Pennsylvania’s regulatory actions were unreasonable or discriminatory against interstate commerce, which they did not find evidence of. Furthermore, they asserted that previous cases involving bridges as channels of trade did not apply here since those involved tolls imposed by Congress itself or under its direct authorization - circumstances absent in this case.