Horizontal federalism refers to the relationships and interactions between states as equal members of the union. Under Article IV of the Constitution states are required provide “full faith and credit” to the laws of other states as well as guarantee the citizens of each state the “privileges and immunities” enjoy by the citizens of other states. Moreover, the Tenth Amendment states that states “may exercise powers not delegated to the federal government. Despite, these understandings, horizontal federalism is one of the more unclear areas of American political authority (Erbsen, 2008).
Based on the arguments from the petitioner in the Tarrant Regional Water District v. Herrmann, Texas’ understanding of the horizontal relationship in the U.S. federal system is: (1) another state’s sovereignty can be ignored through the use of interstate compacts, and (2) state statutes that adversely affect interstate commerce are unconstitutional. In support of this understanding, the petitioner, Tarrant Regional Water District (TRWD) argued that under the Red River Compact, Texas had the right to cross the border and take water from specific streams and waterways in Oklahoma up to the stipulated limit. Moreover, under the terms of the compact, Oklahoma was powerless to stop Texas cross-border appropriation because it was preempted by congressional consent of the Red River Compact. Under this interpretation, Texas understood a state’s fundamental power over its territory or at least its waterways could either be negotiated away or taken away through interstate compacts. Indeed, Texas’ understanding of the horizontal relationship in this context was that states, as a fully functioning political power, has the authority to enter into negotiations with other states and, in essence, enter a contract in which it divests its sovereign authority to another state.
Second, TRWD argued that under the dormant commerce clause, the coequality of states prohibits one state from passing legislation that either favors local interests or discriminates against non-residents by building barriers to interstate commerce. Accordingly, the Oklahoma laws that limited TRWD’s right to obtain the rights to export Oklahoma water to Texas was an unconstitutionally discriminatory regulation against Texas. Here Texas’ understanding of the horizontal relationship was that while all states have sovereignty over their citizens that must be accepted, they cannot use that power to discriminate against the citizens of other states.
Texas’ interpretation of the horizontal relationship as expressed in Tarrant is both consistent and inconsistent with the federal interpretation. First, Texas is correct that under Article I’s interstate compact clause, the drafters of the Constitution understood the importance and necessity of states having the ability to negotiate amongst themselves and enter into cooperative agreements as long as they had the consent of Congress. Moreover, there is nothing in the interstate compact clause that prohibits, as Texas understands, a state from voluntarily giving up a power that it had under the Constitution such as the right to protect its waterways (Erbseb, 2008). But as the Court, in Tarrant made clear, unless there is a clear indication that a state is relinquishing its power, the presumption is that it has not. The idea that state are separate sovereign entities who have broad authority over a range of area except those areas specifically granted to the federal government is evident, as mention in both Article IV and the Tenth Amendment. Moreover, respect of a state’s authority was one of the major issues during the drafting and ratification of the Constitution (Erbsen, 2008). Accordingly, under the federal understanding of the horizontal relationship, states do not easily give up their power and when they do, it is not done ambiguously. Indeed, in Tarrant, the Court states, “we have long understood that as sovereign entities in our federal system, the states possess an absolute right to all their navigable water and the soils under them for their own common use.” Accordingly, for Texas’ understanding of the horizontal relations to be correct in this aspect, they would need to show some affirmative action or wording by Oklahoma that illustrated it was giving up its right to control its waters to Texas. Indeed, the Court points to other compacts that “unambiguously permit signatory states to cross each other’s borders” and which detail “how such cross-border relationships will operate.” According to the Court, the only rational response to the Red River Compact’s silence on giving up control was to follow the traditional and historic understanding of the horizontal relationship which presumes the supremacy of state authority to regulate the activities of its citizens and territories without interference from other states.
Second, under Article I’s Commerce Clause which grants Congress the power to regulate interstate commerce, Texas’ understanding of the horizontal relationship in Tarrant is correct in that states are prohibited from passing laws that burden or discriminate against interstate commerce despite their sovereign powers to regulate all matters within their borders Indeed, the essence of the horizontal relationship is that states’ “coequality and aggregate power” will necessarily lead to competition and friction that if the drafters of the Constitution left to itself would most likely lead to war between the states (Erbsen, 2008). In fact, one of the common frictions between the colonies prior to the ratification of the Constitution was economic protectionism (Erbsen, 2008). As a result, the Constitution, tries to restrain the natural competition of the horizontal relationship by constraining certain natural state prerogatives such as prohibiting actions adverse to interstate commerce. In Tarrant, Texas argued that Oklahoma laws prohibiting TRWD from exporting water not only adversely affected business and commercial opportunities of Texas citizens but also had a negative economic impact for Texas economy as a whole. Accordingly, this was an improper use of the horizontal relationship. The Court however, while not dismissing Texas’ horizontal relationship argument, found that the wording of the compact did not allow Oklahoma to discriminate.
Erbsen, Allan. Horizontal Federalism. Minnesota Law Review, 93. 493-584. 2008. Web.
Podolak, Chuck. "Summary of Tarrant Regional Water District v. Herrmann." 2013. Web. http://sites.nicholas.duke.edu/charlespodolak/files/2013/04/Tarrant-v-Herrmann-Summary.pdf
Tarrant Regional Water District v. Herrmann 656 F.3d 1222 (2013). Web. https://www.law.cornell.edu/supremecourt/text/11-889#writing-11-889_Opinion_3