E. Tate Crymes

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More than just an amenity, “[a river] is a treasure” noted Justice Holmes in a dispute over the waters of the Delaware River. Water is a unique resource in that it is fluid and can move between borders of sovereign states. When water flows across state boundaries, there are often conflicts between the rights of the powerful upstream state and the vulnerable downstream state. Although water rights laws vary across the United States, most eastern states adopt the principle that the right to water is equal for both states. ...

In the Court’s most recent equitable apportionment decision, Florida II, the Court explicitly refused to answer the question of what standard of causation is required for the first element—an actual or threatened injury of serious magnitude caused by upstream water consumption—for the court to equitably apportion state water use. Because of the unique nature of a claim for equitable apportionment, and the reverence the Supreme Court has for mandating resource allocation among sovereign states, a high standard of causation is necessary to effectively balance the harm and the good as required by the Supreme Court’s equitable apportionment precedent. Though the Court refused to decide that issue in Florida II, a “substantial cause” test would most effectively advance the goals articulated by the Court in other recent equitable apportionment cases.

Part II of this article will discuss background information regarding relevant principles of state sovereignty and the original jurisdiction of the Supreme Court to hear cases between states. Part III will focus on applicable equitable apportionment doctrine analysis with illustrations of seminal cases. The clear and convincing evidence standard will be analyzed in Part IV and the standard of causation of the alleged harm will follow in Part V. The Court’s hesitancy to make an explicit holding on the requisite standard of causation will be noted in Part VI. An overall conclusion will reiterate the important points at the very end in Part VII.