Tarrant Regional Water District v. Herrmann (U.S. Supreme Court)

Texas’s Tarrant Regional Water District sought to acquire water from Oklahoma by exercising its rights under the Red River Compact, which governs the allocation and use of water from the Red River Basin among Texas, Oklahoma, Louisiana, and Arkansas. Yet Oklahoma has laws that prohibit the export of water from the state. Tarrant filed a lawsuit against the Oklahoma Water Resources Board to challenge those Oklahoma laws, asserting that Congress’s approval of the Red River Compact preempts Oklahoma’s contrary laws and that Oklahoma’s statutes restrict interstate commerce in water and thereby violate the dormant Commerce Clause. The district court and the Tenth Circuit ruled for Oklahoma. In response to our petition for certiorari, the Court asked the Solicitor General to express the views of the United States on whether it should hear the case; we persuaded the Solicitor General to support the grant of certiorari. The Court then granted our petition, but ultimately affirmed the decisions below.