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SCOTUS Adopts New Oral Argument Format in Case Over Whether Mississippi Must Share Groundwater with Tennessee


The sun shines on the Supreme Court building in Washington D.C. as the Court’s fall term begins.

The Supreme Court of the United States started its new term Monday by hearing oral arguments in Mississippi v. Tennessee, an inter-state dispute over water-use rights. The justices (with the exception of Justice Brett Kavanaugh, who participated remotely) heard live arguments in the courtroom for the first time since the start of the COVID-19 pandemic.

The justices appeared to have learned from their time conducting telephonic oral arguments, as they adopted a kind of hybrid oral argument system for the new term. As in pre-pandemic times, justices were permitted to speak up at a time of their own choosing and fire off questions at counsel. Toward the end of each attorney’s argument, however, the chief justice polled the justices one at a time to elicit further questions. The adjustment made for an ordered and calm oral argument, without the interrupting that was characteristic of the pre-pandemic court.

The case between Mississippi and Tennessee involves groundwater coming from the Memphis Sand Aquifer, which lies on the border between Mississippi and Tennessee. The Magnolia State sued, arguing that Tennessee should not have allowed the Memphis Light, Gas & Water Division to pump groundwater across the border for use in Memphis, and asks for an award of over $600 million in damages. Mississippi argues that Tennessee’s “knowing, intentional, and forcible pumping of groundwater” violates Mississippi’s sovereignty and constitutes a wrongful taking of the state’s “most valuable natural resource.”

Because the dispute is between states themselves, the Supreme Court has original jurisdiction over the dispute (meaning that this is not an appeal from a circuit court, but rather, a case in which SCOTUS will act as fact-finder).

The primary legal issue at hand is whether the Court will apply “equitable apportionment” to this groundwater dispute, as it generally does with disputes over surface water. Under principles of equitable apportionment, states that share a body of water usually have co-equal rights to make reasonable use of that water, so long as its not used inefficiently or wastefully.

Both the court-appointed special master and the federal government support Tennessee’s position in the case: groundwater is an interstate resource to be shared among the states. Mississippi, however, does not want to simply share its groundwater. It argues that fairness principles of equitable apportionment should not be applied in this particular dispute, because what is actually at stake is a property dispute going to the heart of state sovereignty.

In Monday’s oral arguments, the justices appeared to be subdued yet united in their skepticism toward Mississippi’s claim, and Mississippi Deputy Solicitor John V. Coghlan seemed to know he faced an uphill battle as he argued that SCOTUS should reject the special master’s recommendation.

The core of Mississippi’s claim, argued Coghlan, is that by pumping groundwater, Tennessee is invading Mississippi’s sovereign territory. Unlike other water-use disputes over whether one state used more than its fair share of water, said Coghlan, this case asks “do defendants have the right to control ground water while it is located within in Mississippi’s sovereign territory.”

Asking the first question of the day, even before being prompted to do so, Justice Clarence Thomas queried whether Tennessee might make the exact same argument about Mississippi. “Couldn’t Tennessee or Arkansas or Missouri all make the same argument that whenever you pump, you’re causing similar problems for them?” the justice asked.

“They could, and we should be held to the same standard,” answered Coghlan.

Chief Justice John Roberts asked whether siding with Mississippi in this case would create a broad precedent whereby the doctrine of equitable apportionment would apply to all groundwater disputes. Coghlan assured the chief justice that although equitable apportionment should not apply in this case, the Court need not make such a broad ruling. Later, Chief Justice Roberts posed a parallel hypothetical to Coghlin. “In the western states, they have these wild horses or wild burros or whatever they are, and they don’t obey the state lines,” he said.  “Let’s suppose they are a valuable resource,” he continued, asking “If they were in Mississippi and crossed to Tennessee, and Tennessee seized them at that point. Would that be damaging Mississippi?”

Justice Sonia Sotomayor pressed Coghlan on whether Tennessee’s pumping differs from putting up a well or dam, which might also interfere with the natural flow of groundwater to a neighboring state. Coghlan argued that the difference lies in the locus of the contested action. A dam would exist entirely within Tennessee, while the pumping at issue in the instant case actually invades Mississippi’s borders.

Sotomayor appeared exasperated by the case’s lengthy history, as well as Mississippi’s plan for future litigation. Mississippi has argued that if SCOTUS dismisses the case, it should be permitted to amend its complaint, this time arguing that equitable apportionment is applicable.

“You’ve been litigating this case for over 16 years,” the justice remarked. “[District and circuit courts] told you that you have to seek equitable apportionment,” Sotomayor reminded him. “You come here in 2010 and we tell you the same thing. Now this is the third time.” “When is enough enough?” she asked, “When should you be stopped amending and seeking equitable apportionment, assuming you lose?”

Although the justices seemed less skeptical of Tennessee’s position argued by attorney David Frederick, the Court was clearly concerned about the possibility that its decision might encourage more lawsuits relating to groundwater. “You’re asking to extend equitable apportionment groundwater,” Justice Neil Gorsuch commented to Frederick, and asking: “Is every aquifer in the country that might have some interstate effect now going to be part of this court’s original jurisdiction?”

Justice Stephen Breyer said he was “nervous about the question Justice Gorsuch is asking.”  Noting that groundwater exists under every state, Breyer warned, “maybe every state will start all start suing each other — except Alaska and Hawaii.” “Maybe it’s better left to compacts or Congress,” he suggested.

You can listen to the full oral arguments here.

[Image via Chip Somedevilla/Getty Images]

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Elura is a columnist and trial analyst for Law & Crime. Elura is also a former civil prosecutor for NYC's Administration for Children's Services, the CEO of Lawyer Up, and the author of How To Talk To Your Lawyer and the Legalese-to-English series. Follow Elura on Twitter @elurananos