In the case of Missouri, ex rel. Laclede Gas Light Company v. Murphy in 1897, the Supreme Court ruled on a dispute between a gas company and the city of St. Louis over taxation rights. The Laclede Gas Light Company argued that it was exempt from certain taxes due to an agreement made with the city when it was first established in 1857, which stated that they would pay "in lieu of all other taxes" for fifty years after their incorporation date. However, this exemption did not cover any property acquired by them after said date or any improvements made to existing properties. The court held that while such agreements were generally valid under contract law principles (as long as they didn't violate public policy), this particular agreement only applied to property owned by the company at its inception and did not extend to later acquisitions or improvements. Therefore, these could be taxed separately without violating their original agreement with the city. This decision clarified how contractual tax exemptions should be interpreted and applied - specifically emphasizing that they are limited strictly according to their terms and cannot be expanded beyond what is explicitly agreed upon.

In the dissenting opinion for Missouri, ex rel. Laclede Gas Light Company v. Murphy, Justice White argued that the majority's decision was a departure from established principles of constitutional law and an unwarranted intrusion into state affairs. He contended that it was not within the purview of federal courts to interfere with a state's regulation of its own public utilities unless there is clear violation or abuse of power which results in deprivation of property without due process. In this case, he believed no such violation had occurred as Missouri had acted within its rights to regulate gas prices through legislation aimed at preventing unreasonable rates being charged by utility companies like Laclede Gas Light Company. The justice further asserted that if every rate-regulating act were subject to judicial review based on whether it allows businesses reasonable profits, then all regulatory powers would essentially be transferred from legislative bodies to courts - something he deemed inappropriate and contrary to democratic principles.