The US Supreme Court [official website; JURIST news archive] on Monday ruled [opinion, PDF] 7-1 in Montana v. Wyoming [Cornell LII backgrounder; JURIST report] for Wyoming in a dispute with Montana over water rights to the Tongue and Powder rivers. Montana claimed that Wyoming violated the Yellowstone River Compact [text, PDF; materials], which allocates water rights to the two Yellowstone River tributaries, by allowing the construction of water storage facilities and the expansion of irrigation. In 2008, the court appointed [order, PDF; JURIST report] a special master [Cornell LII backgrounder] to investigate and oversee the lawsuit, which was filed directly in the Supreme Court, as it has original [Article III, Section 2 text] and exclusive jurisdiction [28 USC 1251 text] over disputes between states. In his first interim report [text, PDF], the special master determined that Montana failed to state a claim because more efficient irrigation systems are permissible under the compact so long as the conserved water is used to irrigate the same acreage watered in 1950. The court agreed, and, in an opinion authored by Justice Clarence Thomas, overruled Montana's exception to that conclusion:
We conclude that the plain terms of the Compact protect ordinary "[a]ppropriative rights to the beneficial uses of [water] ... existing in each signatory State as of January 1, 1950." ... And the best evidence we have shows that the doctrine of appropriation in Wyoming and Montana allows appropriators to improve the efficiency of their irrigation systems, even to the detriment of downstream appropriators. Montana's allegation that Wyoming has breached Article V(A) of the Compact by allowing its pre-1950 water users to increase their irrigation efficiency thus fails to state a claim. Accordingly, Montana's first exception to the Special Master's First Interim Report is overruled.Justice Antonin Scalia dissented. Justice Elena Kagan took no part in the decision.
Also Monday, the court issued a per curiam opinion [text, PDF] in Bobby v. Mitts [SCOTUSblog backgrounder]. The court reversed the decision of the US Court of Appeals for the Sixth Circuit, which had ruled in favor of an Ohio death row inmate. Relying on it's decision last year in Smith v. Spisak [JURIST report], the court ruled that the jury instructions did not violate the defendant's rights.