In the case of Western Distributing Co. v. Public Service Commission of Kansas et al., 1931, the U.S Supreme Court dealt with a dispute over interstate commerce and state regulation. The Western Distributing Company, an oil distributor based in Colorado, was transporting fuel across state lines into Kansas without having obtained a certificate from the Public Service Commission of Kansas (PSC). The PSC argued that it had jurisdiction to regulate this activity under its authority to oversee public utilities within the state's borders. However, Western contended that such regulation violated their rights under federal law governing interstate commerce. The Supreme Court sided with PSC ruling that states have regulatory power over businesses operating within their boundaries even if those operations involve some degree of interstate commerce as long as they do not interfere directly with federal control over such commerce or discriminate against it unfairly. This decision upheld states' rights to regulate local aspects of economic activities crossing their borders while also affirming federal supremacy in managing broader aspects of national economy.

In the dissenting opinion for Western Distributing Co. v. Public Service Commission of Kansas, it was argued that the majority's decision to uphold a state law requiring truckers to obtain certificates of convenience and necessity before operating within the state was an overreach of states' rights and violated principles of free commerce. The dissenting justices contended that such regulation should be left up to federal authorities rather than individual states, as interstate commerce is inherently a national concern. They further asserted that this type of legislation could lead to protectionism among states, with each one setting up barriers against trucks from other jurisdictions in order to protect their own industries - something they believed would ultimately harm both consumers and businesses alike by limiting competition and driving up prices.