In the case of Colorado v. Kansas et al., 1943, the U.S. Supreme Court was asked to resolve a dispute between states over water rights from the Arkansas River. The river originates in Colorado and flows through Kansas into Oklahoma and Arkansas. Both Colorado and Kansas claimed rights to use its waters for irrigation purposes, leading to conflict as both states experienced drought conditions during this period. The court had previously ruled on similar interstate disputes using principles of equitable apportionment - essentially dividing up resources fairly based on each state's needs and uses. However, in this case, it found that there wasn't enough evidence presented by either side to make such an allocation. Instead of making a definitive ruling about how much water each state could take from the river, the court decided that more investigation was needed before any decision could be made regarding equitable distribution or whether one state’s usage was causing harm to another’s ability to utilize their share effectively.

In the dissenting opinion for Colorado v. Kansas et al., Justice Frank Murphy argued that the majority's decision to deny Colorado's request to increase its use of Arkansas River water was too rigid and failed to consider changing circumstances. He believed that the 1907 decree, which allocated water rights between states, should not be considered as a final judgment due to evolving conditions such as population growth and technological advancements in irrigation techniques. Instead, he suggested a more flexible approach where equitable apportionment could be adjusted based on current needs and usage patterns rather than strictly adhering to past agreements. Furthermore, he expressed concern about potential harm caused by denying states like Colorado access to additional resources necessary for their development.