In the case of Pacific Telephone & Telegraph Company v. Kuykendall, the Supreme Court ruled in favor of Pacific Telephone & Telegraph Company (PT&T). The dispute arose when Washington state's Director of Public Works attempted to enforce a law that required PT&T to obtain approval before constructing any new lines or facilities. PT&T argued that this law was unconstitutional as it interfered with interstate commerce and violated their rights under the Fourteenth Amendment. The court agreed with PT&T, stating that while states have power over local matters, they cannot interfere with interstate commerce which is regulated by Congress under the Commerce Clause of the Constitution. Furthermore, they found that requiring prior approval for construction projects placed an undue burden on PT&T's ability to conduct business and thus infringed upon their Fourteenth Amendment rights.

The dissenting opinion in the case of Pacific Telephone & Telegraph Company v. Kuykendall argued that the majority's decision was an overreach of federal power and a violation of states' rights. The dissenters believed that Washington State had the right to regulate its own public utilities, including telephone companies like Pacific Telephone & Telegraph. They contended that it was not within the jurisdiction of the Supreme Court or any other federal entity to interfere with this state-level regulation unless there were clear constitutional violations involved, which they did not believe existed in this case. Furthermore, they disagreed with the majority's interpretation of interstate commerce laws and felt their ruling could set a dangerous precedent for future cases involving state versus federal authority.