MISSISSIPPI, Plaintiff, v. TENNESSEE, CITY OF MEMPHIS, TENNESSEE, AND MEMPHIS LIGHT, GAS & WATER DIVISION, Defendants
Interviewer(s): Clarence Thomas, Stephen G. Breyer, Elena Kagan, John G. Roberts, Jr., Neil Gorsuch, Brett M. Kavanaugh, Amy Coney Barrett, Sonia Sotomayor
Interviewee(s): Frederick Liu, John V. Coghlan, David C. Frederick

John G. Roberts, Jr.: We will hear argument first this morning in Original Case 143, Mississippi against Tennessee. Mr. Coghlan.

John V. Coghlan: Mr. Chief Justice, and may it please the Court: The Court should reject the Special Master's conclusion that equitable apportionment is Mississippi's sole remedy because it's a remedy that redresses the wrong injury. Mississippi does not claim that Defendants are taking more than their fair share of groundwater.

Rather, Mississippi's case turns on a different question: Do Defendants have the right to control groundwater while it is located within Mississippi's sovereign territory? And the Court has answered this question in Tarrant Regional Water District versus Herrmann.

There, in considering an interstate surface river that had already been apportioned, the Court recognized an injury other than that of an upstream state harming a downstream state by taking too much water. Specifically, the Court recognized that one state may not divert water from another state's sovereign territory absent a waiver of that sovereignty. And, here, it's undisputed that Tennessee is diverting groundwater from Mississippi without Mississippi's permission and they do so knowingly.

In the 1960s, the U.S. Geological Survey warned them it was happening. But rather than stop, Defendants opened new well fields within three miles of the border and substantially increased their pumping. As of 2014, when Mississippi filed its complaint, they had suctioned more than 400 billion gallons of groundwater across the border.

They've increased the cost of Mississippi's own groundwater pumping.

And by their own admission, Defendants' pumping is draining an overlying surficial aquifer that record evidence indicates is pulling contaminants down into the aquifer at issue in this case. Now the Special Master, in reaching its conclusions, asked whether the Middle Claiborne Aquifer was an interstate resource. This was the wrong question to ask because the answer doesn't matter.

Even if the aquifer is an interstate resource, Mississippi still possesses sole and exclusive control over groundwater within its sovereign territory, as recognized in Tarrant and ensured by the Constitution, and Defendants cannot force groundwater across the border without violating this sovereignty. I welcome the Court's questions.

Clarence Thomas: Well, counsel, you seem to complain about Tennessee pumping water from Mississippi, but you admit that Tennessee does not enter across the border into Mississippi, isn't that correct?

John V. Coghlan: Well, Justice Thomas, we acknowledge that their wells are physically --

Clarence Thomas: Okay.

So -- but the case that you cite as an intrusion from -- I think it's Tarrant or Tarrant -- wasn't that a cross-border situation?

John V. Coghlan: Well, yes, Your Honor, and we would say that this is a cross-border situation too.

So we certainly acknowledge that their wells are physically located in Tennessee, but the pumping is physically crossing the border, unnaturally changing the pressure levels in this aquifer.

Clarence Thomas: But isn't that true of any well? I mean, let's say it was a lake and Tennessee was pumping water on its side of the lake.

Couldn't you argue that technically it was drawing water from Mississippi?

John V. Coghlan: I -- I think so, Your Honor, and I think the -- the key is where -- what is the range of the unnatural effect that is controlling the water? And so, here, it's -- it's undisputed that there -- these wells create cones of depression that are measurable, limited, and controllable and predictable.

And so Tennessee is exercising control over the groundwater within that area.

Clarence Thomas: But couldn't Tennessee make the exact same argument about you? Couldn't Tennessee, Arkansas, Missouri all make the same argument that whenever you pump you're causing similar problems for them?

John V. Coghlan: They certainly could, and we should be held to the same standard, Your Honor.

We don't believe that Mississippi is pulling any groundwater or exercising control over groundwater extraterritorially.

Certainly, if that was the case, Mississippi should be held to the same standard.

Clarence Thomas: Lastly, and I'll be done, do you have any cases that suggest that -- or to support your argument on that point, that the mere fact that you draw from the same well without entering another state is actionable?

John V. Coghlan: Well, Your Honor, I -- I would point back to -- to Tarrant in this sense, that Tarrant doesn't specifically say that there has to be a physical crossing of the border. Tarrant focuses on the water and who's exercising control over the water. And so we would -- I would contend that, here, it's Tennessee exercising control over this water unnaturally while it was within Mississippi, essentially creating a vacuum and intentionally putting these vacuums right next to the border to exercise a limited area of control over water and pull it out of Mississippi into Tennessee.

Clarence Thomas: All right.

John G. Roberts, Jr.: Counsel, I think your position comes down to arguing that equitable apportionment is a remedy that should be used only in the case of interstate waters, in addition, you know, to the salmon, who kind of go with the flow.

John V. Coghlan: Mr. Chief Justice, that's not our argument, and I think that Tarrant makes this point because Tarrant dealt with an interstate surface river that had already been apportioned.

But I think the problem is equitable apportionment redresses a different type of injury.

It addresses a case where states are acting entirely within their own sovereign borders, the unnatural taking of water is occurring entirely within a state's sovereign borders. This is different because this is a state crossing the border, exercising control over that resource beyond the border, so that's why I say it doesn't matter --

John G. Roberts, Jr.: Well, what other cases would you -- putting aside water, what other cases would you admit are subject to equitable apportionment?

John V. Coghlan: Your Honor, I'm not sure, and I'm not sure the equitable apportionment should or should not apply as a concept to groundwater.

I think there are reasons why, based on the nature of groundwater, it might not make sense. But I think the Court doesn't need to address that question about whether or not equitable apportionment should apply to groundwater because, as I say, this is a different type of injury.

This is an injury where one state is reaching across the border and exercising control --

John G. Roberts, Jr.: Well --

John V. Coghlan: -- beyond its sovereign territory.

John G. Roberts, Jr.: -- putting aside your reaching across the border, I mean, in -- in the absence -- you do -- you concede, don't you, that the aquifer flows from Mississippi into Tennessee?

John V. Coghlan: We -- we concede that there is some water that crosses the border, yes.

John G. Roberts, Jr.: Well, I suppose then you're -- you're not saying that there's no equitable apportionment of that water?

John V. Coghlan: I think, Your Honor, our point is that whether or not aquifers and groundwater should be subject to equitable apportionment is not the legal issue that we're presenting before the Court. What we're presenting is does Tennessee have the right to control the resource beyond Tennessee's sovereign boundaries in Mississippi when Mississippi has not waived its sovereign right over control of that groundwater.

Elena Kagan: I'm not sure I understand that, Mr. Coghlan.

I mean, you're not now saying that this is not an interstate water.

You're conceding that it is an interstate water, is that correct?

John V. Coghlan: I don't know that we're conceding it, Justice Kagan.

I --

Elena Kagan: You're saying that you win even if it is an interstate water --

John V. Coghlan: That's --

Elena Kagan: -- is that correct?

John V. Coghlan: -- that's correct.

Elena Kagan: Okay.

So you're saying it's irrelevant whether it's an interstate water or not?

John V. Coghlan: That's correct.

Elena Kagan: So let's assume that it is an interstate water.

John V. Coghlan: Okay.

Elena Kagan: And you're saying that the reason you should win is because -- is because what? Because Mississippi is essentially doing something unnatural to have access to that interstate water? What --

John V. Coghlan: I'd say, Your Honor, it's that Tennessee --

Elena Kagan: Tennessee, excuse me.

John V. Coghlan: That Tennessee is exercising control over groundwater while it is located within Mississippi's sovereign territory.

Elena Kagan: Well, but Tennessee is doing things, I think you admitted, in -- in -- in one of the questions that Justice Thomas put to you -- Tennessee is acting entirely within its own borders.

It is having effects on Mississippi, but that's the case with respect to people using a flowing river, that if there's a -- a flowing river, Tennessee might be taking water from it, which has effects in Mississippi. So why is it any different?

John V. Coghlan: Justice Kagan, where I would disagree with you is that Tennessee is acting entirely within its own borders.

Their -- their wells are physically located in Tennessee, but this pumping is creating a unnatural area of effect that's predictable, measurable, and controllable, and that area of effect is having physical effect, unnatural --

Elena Kagan: Well, it's have --

John V. Coghlan: -- physical effects --

Elena Kagan: -- it's -- it's predictable, measurable, and controllable when an upstream state takes a lot of water from a river that that will leave the downstream state with less water.

All of that is predictable in the exact same way that one state is harming another, and yet we turn to equitable apportionment to deal with that.

John V. Coghlan: And I think, Your Honor, the difference as -- as I -- in this case is that in all of the Court's equitable apportionment cases, the state who's, you know, unnaturally having an effect on the water by taking and removing water is acting, and the effect of that is occurring -- the direct effect of that is occurring entirely within the state's sovereign territory and that whether or not the water ultimately doesn't reach the downstream state because it doesn't flow there is -- is incidental, whereas, here, there is a direct intentional effect. The -- the -- the purpose of pumping is to move water.

And Tennessee is putting these wells next to the border, creating a vacuum, and of -- of a measurable area of effect, and intentionally pulling the water out of Mississippi and exercising control, direct control I would say, over that groundwater while it is within Mississippi's sovereign territory. And I think --

Sonia Sotomayor: Counsel, can you please explain to me how that's different from a dam, if Tennessee built a dam and put it on the Tennessee side, it's completely on its side, and it's interfering with the natural flow of water to Mississippi? So how is that different than putting a well that interferes with the natural flow of the groundwater?

John V. Coghlan: Well, Justice Sotomayor, I don't know that it would be appropriate to -- to dam a water, but the difference I would say is -- is this: that creating a dam within your own sovereign territory is an action occurring within your own sovereign territory.

The -- the -- the physical direct effect of it is within Tennessee if that's what's happening. Pumping here is exercising control over the water while it is physically located in Mississippi.

In -- in the example of the dam, the physical control over the water is occurring entirely within Tennessee. Here, it's occurring within Mississippi's sovereign territory, where Mississippi has the exclusive right to exercise control over the groundwater.

Sonia Sotomayor: May I turn your attention to an issue you didn't mention, which is whether you should be given leave to amend or not? That is what your -- the other side is pointing to as their exception. Could you tell me -- you've been litigating this case for over 16 years.

You started in the Fifth Circuit.

You went to the district court, you went to the circuit court; both courts told you you've got to seek equitable apportionment.

You come here in 2010. We tell you the same thing. Now this is the third time you've done this.

This -- this time you explicitly disclaim any claim for equitable apportionment. When is enough enough? When should you be stopped from amending and seeking equitable apportionment, assuming you lose? But it is a question that's open in this case.

John V. Coghlan: Well --

Sonia Sotomayor: It's only an assumption I'm working from, but when is enough enough?

John V. Coghlan: Well, Your Honor, I think there's a recognition in equitable apportionment cases that it's prospective, and it's for future injury.

It's not to rectify past injury.

That's part -- that's part of the reason why we think it's the wrong remedy here. We also think it doesn't redress the injury over sovereign control of water.

But, based on the nature of the remedy and that it is prospective only, I think there's a recognition that states should always have the right to be able to pursue that -- that remedy, particularly here, where, in the interim, Tennessee continues to pull groundwater out of Mississippi. I think it would be inequitable to prevent us from --

Sonia Sotomayor: Well, why shouldn't we just leave that question alone? Why should we just not decide this case, whatever the decision is, and not decide whether to grant -- to grant permission or not and, assuming you finally say you're going to amend or do amend, let you figure out what's equitable at that time or not?

John V. Coghlan: Well, I -- I think, Your Honor, again, setting aside the fact that we think equitable apportionment is the wrong remedy for -- for this case --

Sonia Sotomayor: So that goes to my -- begs my question --

John V. Coghlan: Yeah.

Sonia Sotomayor: -- which is, if you think it's the wrong remedy, can you plead it, number one? Will you plead it, number two?

John V. Coghlan: If -- if the Court disagrees with us and finds that equitable apportionment is the only remedy available to Mississippi, we would still want the option to -- to pursue that.

Even if it's -- we think it would be incomplete as a form of relief, we would want to obtain whatever relief is possible for -- for Mississippi.

John G. Roberts, Jr.: Counsel, you emphasized in your -- your answers so far the concept of physical control of the aquifers.

In Mississippi, it's theirs to control. You know, in the western states, they have these, I don't know, wild horses or wild burros, whatever they are, and they don't obey the state lines and they're wandering around and they -- let's just say they go from, you know, New Mexico to wherever. Let's suppose that they're -- I know they're pests, I guess, in some places, but let's suppose they're a valuable resource.

If they were in Mississippi and crossed into Tennessee and Tennessee seized them at that point, would that be damaging Mississippi, or could Tennessee say, look, they're on our territory, they're under our physical control, we can exercise dominion over them, period?

John V. Coghlan: Mr. Chief Justice, I think, if they're exercising control within Tennessee, that is distinct from what's happening here, where there's control --

John G. Roberts, Jr.: Well, I don't care if it's distinct from what's happening here or not.

I'm just wondering if -- I -- I would suggest that that's at least in some sense an interstate resource. Normally, under our precedents, those are subject to equitable apportionment.

But -- but you would say under your theory that, no, that Tennessee could take all the value of that interstate resource just because it happened to be under Tennessee -- in Tennessee under that particular point?

John V. Coghlan: Mr. Chief Justice, I -- I -- I don't know the answer to that question, but I think the point is this: whatever the limits of that sovereign control are -- and we're not saying here that Mississippi's sovereign control over groundwater is unlimited. Certainly, Congress can place limits on it. This Court, acting appropriately, can place limits on it.

Our point is that Tennessee may not limit it in Mississippi by exercising control over it while it is within Mississippi.

John G. Roberts, Jr.: So I -- so it sounds to me like you're not going to give me an answer on the wild horses?

John V. Coghlan: Well, Mr. --

John G. Roberts, Jr.: It's an interstate resource that goes back and forth between two different states.

You seem to say that if it's in one state, that's theirs.

If it's in the other, you know, it's -- it's that state's.

And I'm positing a resource that migrates between the two states because some people might think that's what's at issue here.

John V. Coghlan: And, Mr. Chief Justice, I -- I apologize.

Your question is whether or not Tennessee could take -- capture all the horses --

John G. Roberts, Jr.: Yeah.

John V. Coghlan: -- while --

John G. Roberts, Jr.: Whoever -- you know, in the spring or whenever, they -- they go to Mississippi, and then, in the fall, they go to Tennessee, and can Tennessee, say, just grab -- round them up and say they're ours?

John V. Coghlan: While they're in Tennessee?

John G. Roberts, Jr.: While they're in Tennessee.

John V. Coghlan: I would suggest yes, they could.

Whether or not they could do so to the extent that they would preclude all of those horses from going back to --

John G. Roberts, Jr.: Yeah, every last one they -- they grab.

John V. Coghlan: Your Honor, probably not.

But I -- I would suggest that the difference in the example you're suggesting is -- is that which distinguishes equitable -- all the Court's equitable apportionment cases from -- from that here, which is that in the example Your Honor is, you know, suggesting, Tennessee is acting entirely within Tennessee's borders. It's not acting extra -- extraterritorially. And I'd say that is what distinguishes the case here from Your Honor's example and -- and from all the Court's equitable apportionment cases.

Stephen G. Breyer: So what -- what -- I have the same kind of question.

My understanding -- and you have to -- it's very elementary.

I mean, I think water falls from the sky.

Some of it's evaporated back.

Others of it goes into oceans or lakes or streams.

A huge amount goes under water -- underground. It's groundwater, and it runs all over the place.

That's why I like the wild horses.

My idea of that groundwater is it's going all over the place.

John V. Coghlan: Yes.

Stephen G. Breyer: So what's the standard? Are there any cases? What's the standard when one state takes some of that running-around groundwater that another state says, oh, no, you should've stayed here? It sounds to me -- you know, San Francisco has beautiful fog.

Suppose somebody came by in an airplane and took some of that beautiful fog and flew it to Colorado, which has its own beautiful water -- air.

And somebody took it and flew it to Massachusetts or some other place. I mean, do you understand how I'm suddenly seeing this and I'm totally at sea? It's that the water runs around.

And whose water is it? I don't know.

So you have a lot to explain to me, unfortunately, and I will forgive you if you don't.

John V. Coghlan: Well, Justice Breyer, I would say this: We're not claiming here that Mississippi owns the water in a sense of absolute title to the water.

What we're talking about is the -- the right to exercise control over the resource while it is within the -- the sovereign territory and the borders of Mississippi. And Mississippi is not trying to prevent the water from flowing naturally or to go across the border or -- or prevent the wild horses in the Chief Justice's hypothetical from going across the border. What we're saying is Tennessee does not have a right to exercise any control over them while -- or over -- control over the groundwater while it is within Mississippi. And what -- so what we're proposing is that states can, you know, withdraw groundwater from within as long as the physical effects -- and this is something that's measurable and predictable, as I said -- as long as the physical effects of those pump -- that pumping does not encroach and affect the water and control the water outside the -- or in -- in a sister state.

Elena Kagan: Yeah, but you're saying that the question is whether there's an extraterritorial action.

But there has not been a trespass.

There has not been pumping on Mississippi's land.

What there has been is actions on Tennessee's land that have a measurable and predictable effect.

That is often true when it comes to water, that one can take action in one state and have effects in another state.

I mean, all of our cases in this area are premised on that. So why is it any more true in this case than in any other that there's extraterritorial action as opposed to extraterritorial effects?

John V. Coghlan: Your Honor, because I would say that there's -- the intent of pumping is to move water and to exercise control over the groundwater in this case.

And so I come back to the fact that it's -- it's measurable and predictable because that's the area over which states know they're going to be impacting and having a direct effect on the groundwater. And, you know, what Mississippi -- what Tennessee and Defendants seem to want to say is, well, if there was a pipe that crossed the border and that made -- made a physical intrusion of space, that Mississippi would win and this case would be different when a pipe doesn't actually do anything to water.

It's the pumping that controls the water and causes the water to move from one place to another. And so to say that, well, you need to have a pipe or some sort of physical intrusion of space for this case -- in this exercise of control over the water to be actionable, we think, would elevate form over substance because they don't need a pipe to exercise control over this groundwater.

Amy Coney Barrett: Okay.

I have a follow-up on Justice Kagan.

Brett M. Kavanaugh: Mr. Coghlan --

Amy Coney Barrett: I think what you're asking -- or what she's asking you and pointing out is that it wouldn't work this way if we were talking about water that was above ground.

So what is your argument -- and this is kind of what Justice Kagan asked you at the beginning. What is your argument for treating the groundwater differently? I mean, how much of it depends on your assertion that, well, it travels interstate but very slowly, it can take centuries to move from Mississippi into Tennessee? I mean, is it the speed at which the water moves that matters here? And if so, when is it so fast that actually it falls into the -- the aboveground --

John V. Coghlan: Well --

Amy Coney Barrett: -- kind of category?

John V. Coghlan: Well, Your Honor, our view is that this principle would apply equally to groundwater, to surface water, to -- to other types of resources.

And we think that's what the Court recognized in Tarrant when it recognized this concept when dealing with an interstate surface river that had already had the remedy of apportionment applied and recognizing that there was a different type of injury because, in that case, Texas was seeking to divert water and exercise control over it while it was within Oklahoma's sovereign territory. So I -- I would posit that it does -- it does not matter that the water here is groundwater in the subsurface.

The principle should apply equally and we think the Court has found it to apply equally with surface water in Tarrant.

Neil Gorsuch: I'd like to --

Brett M. Kavanaugh: Mr. Coghlan --

Neil Gorsuch: Oh, go -- go ahead, Justice Kavanaugh.

John G. Roberts, Jr.: Justice -- Justice Kavanaugh.

Brett M. Kavanaugh: The amicus brief of eight states says that your position would "inject dangerous uncertainty into established systems of natural resource management and undermine an established process to resolve disputes over a natural resource." So I just wanted to get your response to those states which seem to suggest that your position would cause a lot of problems in how to manage these resources.

John V. Coghlan: Well, Justice Kavanaugh, the states' amicus is premised on the notion that there is no known duty.

And we would posit there is a known duty here.

The Court has recognized it in -- in Tarrant, is that states can only exercise control, sovereign control, over a resource within their own borders. So I think what we're asking to do is for the Court to just simply extend the principles recognized in Tarrant to the -- to the case -- which are known duties, to the case here. And I think I would respond to the western states by saying, what would happen if Tennessee wins? And I think the danger there is -- is what we're already seeing here, where you have both Mississippi and Tennessee pumping on each side of the border, trying to have a tug of war over this groundwater at issue, unnaturally draining the -- the aquifer and damaging it when -- if, based on the nature of groundwater, if both states pumped away from the border, neither state would have any impact whatsoever on the groundwater within the -- the neighboring state. And I think that's unique about -- about groundwater.

But -- but Tennessee could have gotten all the groundwater and pumped as much groundwater as it wanted and had zero effect on the groundwater in Mississippi if it had -- if the cones of depression were not crossing the border.

And so this is an area where it's distinct from surface water because there isn't this natural leveling out of water when -- when you take it out.

There's only a limited area of effect when you're pumping groundwater outside of which there's no impact whatsoever on the rest of the aquifer. And I think that's another -- that's a reason why, conceptually, equitable apportionment may not make sense to apply to groundwater, because it's not about the amount of groundwater coming out; it's purely about where that groundwater is -- is -- is coming from. But, to -- to -- to answer your question directly, Justice Kavanaugh, we do not believe that there would be the detrimental effects that the western states complain of.

John G. Roberts, Jr.: Counsel, I just have one additional question.

If you prevail, then, presumably, Tennessee could bring -- or could bring a counterclaim against you in those situations where your wells take water from Tennessee, right?

John V. Coghlan: That is true, Your Honor, but I --

John G. Roberts, Jr.: Okay.

Then -- then, if they do, presumably, the normal thing would be I'd take whatever you owe -- Tennessee owes you and whatever you owe Tennessee and set it off against the other and that's what would happen, right?

John V. Coghlan: I -- it -- it could, Your Honor.

I think that it would be a motivating factor for states to come and negotiate interstate contact.

John G. Roberts, Jr.: Okay.

So, if it could, that starts to sound a lot like equitable apportionment.

How is it different at the end of the day?

John V. Coghlan: Well, in the sense that it would motivate states to -- to come and negotiate, we think it would have -- it would have -- be similar to equitable apportionment in -- in that respect.

John G. Roberts, Jr.: Thank you. Justice Thomas?

Clarence Thomas: I have no further questions.

John G. Roberts, Jr.: Justice Breyer? Justice Alito? Nothing? Justice Kagan? Justice Gorsuch?

Neil Gorsuch: I -- I do have one quick question just to follow up on Justice Sotomayor's line of questioning to you, counsel. Suppose you fail to prevail here today.

I'm -- I'm wondering what we do next. The Special Master recommended that we grant leave to amend to add an equitable apportionment claim.

But we don't actually have a motion for leave to amend before us.

And we have a standard that has to be met among other things, whether it's a logical outgrowth of the existing litigation, timeliness, as Justice Sotomayor alluded to, and I'm just wondering what you would have the Court do should you fail to prevail?

John V. Coghlan: We'd ask the Court to -- to grant us leave to amend, and, of course, the Court could --

Neil Gorsuch: Have you -- have you moved? Have you sought to meet the standards? I -- I -- I haven't seen that in the papers before us.

John V. Coghlan: We -- we have not yet, Justice Gorsuch.

Neil Gorsuch: So, again, what would you have this Court's judgment line look like should you fail to prevail? We wouldn't grant leave to amend because there's no motion pending before us.

Do we just say, as Justice Sotomayor said, nothing?

John V. Coghlan: Justice Gorsuch, we think the Court could grant leave to amend but certainly reflect the principles you -- you just mentioned, that if Mississippi does not behave timely or -- or does not file a -- a proper motion, that the Court could obviously deny that.

Neil Gorsuch: So give you a certain number of days in which to present the Court with a proper motion? Is that the suggestion?

John V. Coghlan: I wouldn't put a specific number and obviously would defer --

Neil Gorsuch: Of course not.

No -- no -- no one wants a deadline.

But should -- give you an opportunity within a reasonable period of time, and we might set a deadline for a motion.

Is -- is that -- is that your suggestion?

John V. Coghlan: We would -- I think the Court certainly could do that.

And -- and whatever number the Court would feel would be reasonable, we would act within that period.

Neil Gorsuch: Thank you very much, counsel.

John G. Roberts, Jr.: Justice Kavanaugh.

Brett M. Kavanaugh: Just picking up on that, isn't your position that you want to preserve the right to seek equitable apportionment into the future even if you don't seek it now, or am I misunderstanding that?

John V. Coghlan: I -- I -- I think it's both, Justice Kavanaugh.

We would like the opportunity to -- to replead in this matter, but also, because equitable apportionment is a prospective remedy only, we would want the opportunity to pursue that in the future in a new action if -- if needed.

Brett M. Kavanaugh: Thank you.

John G. Roberts, Jr.: Justice Barrett?

Amy Coney Barrett: None.

John G. Roberts, Jr.: Okay.

Thank you, counsel. Mr. Frederick.

David C. Frederick: Thank you, Mr. Chief Justice, and may it please the Court: Tennessee has lawfully pumped groundwater out of the Middle Claiborne Aquifer on its side of the border for more than 130 years.

The Special Master correctly recommended dismissal of Mississippi's complaint but erred in suggesting that Mississippi be freely granted leave to amend. First, the Equitable Apportionment Doctrine provides the exclusive remedy for complaints about the usage of water that flows from one state into another and the actions in one state affect interstate water flow. Mississippi's claim for more than $600 million in damages, therefore, must be dismissed. Mississippi's principal argument in response is that the aquifer water flows slowly. But this Court has never conditioned the application of the Equitable Apportionment Doctrine on water velocity. Here, even Mississippi's expert acknowledged that in predevelopment conditions, more than 37 million gallons of water per day flowed out of Mississippi and into adjoining states. Second, the Master did not consider how this case would fundamentally change if Mississippi were freely allowed to amend to plead an equitable apportionment action at this stage after disavowing an apportionment claim for the last decade. Nor did the Master consider that Mississippi can show no injury at all from Tennessee's water withdrawals.

The undisputed facts are the aquifer's water volume in the greater Memphis and northern Mississippi area has changed very little in the past 100 years. The aquifer is fully saturated and in a state of equilibrium.

And Mississippi has increased its own pumping dramatically and can extract all the water it needs. Mr. Chief Justice, I welcome the Court's questions.

Clarence Thomas: Mr. Frederick, counsel for Mississippi says that if you simply moved your pumps away from the border, all would be well.

What do you make of that?

David C. Frederick: Well, two things. There was testimony on this at the trial. Dr. Sprule was asked that question and said that Memphis could engage in a massive relocation, and then Mississippi's other expert, Mr. Wiley, said that it would have no appreciable effect on the cone of depression. Dr. Sprule, on cross-examination, conceded that Mississippi's own pumps are closer to the border than those in Tennessee.

And when Dr. Waldron, our expert, testified, he said that that pumping was causing a reversal in the change in the water flow and that Mississippi was, in fact, intercepting -- that was his words -- water that would have flowed from Mississippi to Tennessee in its natural state.

Clarence Thomas: And you oppose amending the complaint here to include apportionment, equitable apportionment.

What is to stop Mississippi from simply filing a new motion in this case and starting all over?

David C. Frederick: Nothing would stop it, but Mississippi would have to meet the standards for a material change in circumstances that would warrant this Court's consideration of an equitable apportionment claim. In the case of Colorado versus Kansas, decided in the early 1940s, this Court said that the standard was a material change in circumstances.

That, of course, was the long-running dispute over the Arkansas River. And what the Court said was that if that material change in circumstances has not occurred, then denial of a motion for leave to file a complaint is the appropriate disposition.

Clarence Thomas: Thank you.

Sonia Sotomayor: Mr. Frederick, you claim that the equitable apportionment is the exclusive remedy.

The amici law professors say it shouldn't be, that a nuisance action could also be appropriate. If all they wanted was to stop you from drawing water because the way you're drawing it harmed the aquifers, which is, I think, what I heard them say earlier, why wouldn't a nuisance action be appropriate?

David C. Frederick: A nuisance action would be appropriate if there was damage to the water or if there was some issue of subsidence or other water quality.

I think this Court's case in City of Milwaukee is representative of a cross-boundary tort. But what they are complaining about is our usage of the water that flows in interstate --

Sonia Sotomayor: So it's a --

David C. Frederick: -- waters.

Sonia Sotomayor: -- question of how they pleaded?

David C. Frederick: I think that's correct.

And in the nuisance context, the law professors don't say exactly how you would administer a nuisance claim under what they are talking about.

And I would point out that there was evidence at the trial about the absence of subsidence or any degradation of water quality. We presented that in our Defendants' Proposed Findings of Fact Numbers 246 and 47 on page 126A.

Sonia Sotomayor: One last question. What does a material change mean to you? What would qualify?

David C. Frederick: I think what would qualify is if Mississippi was able to plead plausibly and with the suggestion that clear and convincing evidence would follow that it was unable to extract water, that it had to engage in significantly increased costs in order to pump, that it suffered a degradation in water quality or that there was evidence of subsidence in the aquifer as a result of pumping. Those would be of the type that you would measure their significance based on the classic standard that you would look --

Sonia Sotomayor: Given the way this has been litigated, those issues have not actually been decided by anyone.

David C. Frederick: They haven't been decided, but they're --

Sonia Sotomayor: So why should we even say don't amend until there's a material change? Because we don't even know what the baseline is right now.

David C. Frederick: Well, what you would say is that -- and I think to your earlier question to my friend, I think you would say nothing.

Where the Special Master erred was in suggesting that there be a free motion to amend without actually following through the necessary steps, a motion satisfying of the standard for a material change in circumstances. And you do have cases on this, Your Honor.

Nebraska versus Wyoming, which looked at the question of what constitutes a fundamentally different change of character of the claim, is directly on point, as is the Colorado versus Kansas case. So you do have standards.

It would be Mississippi's burden, of course, to prove that since 2010, when this Court denied Mississippi's complaint in the alternative for an equitable apportionment, that circumstances had changed sufficiently to warrant allowing it to go forward.

Elena Kagan: Mr. Frederick, suppose that Mississippi had an entirely intrastate lake that was near the Mississippi/Tennessee border but was -- all the borders of this lake were in Mississippi.

And suppose -- and suppose that there was some newfangled technological way of Tennessee helping itself to the waters of that lake. Would that be an equitable apportionment claim, or, in that case, would Mississippi have a different kind of action?

David C. Frederick: I think it would have a different kind of action.

The Equitable Apportionment Doctrine has applied to interstate bodies of water in which there is flow, there's natural flow.

And under your hypothetical, Justice Kagan, there would be no interstate character to the water.

Elena Kagan: Is -- is there such a thing as, when you're dealing with groundwater, looking at groundwater and saying that it moves so slowly, with the consequence of transferring so little water between these states, that we should treat it as my hypothetical rather than treat it in the same way as, say, an interstate river?

David C. Frederick: There was no evidence at the trial, the five-day trial, about that, although there was a lot of questioning about that concept, and all of the hydrologists acknowledged a couple of key facts for the court. One is there is no physical barrier between the water in the ground under Tennessee and under Mississippi.

There is no distinction in the subsoil surface, the sands and the composition.

It is one continuous hydrological unit.

That was acknowledged by all five hydrologists who testified. And so what you would be looking at there, I think, is a situation that would be quite different than the aquifer that we have before us here. Now, on the volume question, Justice Kagan --

Elena Kagan: I mean -- I mean, maybe that would be true -- you -- you started by saying, oh, look, this is, like, 37 million -- what was it, 37 --

David C. Frederick: Thirty-seven million gallons per day.

Elena Kagan: Right.

And -- and -- and you suggested that that's a relevant fact such that if there weren't 37 million, if there were 37,000 or if there were 37, we should maybe have a different way of analyzing this question, is that right?

David C. Frederick: I don't think so because, in the interstate lake hypothetical that Justice Thomas, I believe, posed, you'd still have the same kind of phenomenon.

Water in its natural state is always going to be moving.

Water molecules will be moving. Now how quickly they move ought to be irrelevant to the application of the Equitable Apportionment Doctrine for a couple of reasons. Legally, the Court has never said that, and in the Oregon versus Washington case, where it looked at whether or not the anadromous fish -- sorry, Idaho case, the anadromous fish, those fish were out at the ocean for years before they came back to spawn. And the Court has also considered situations where rivers have run dry for long stretches of time before there's any water flow. It nonetheless has held that the Equitable Apportionment Doctrine applies. But, on the volume point, Justice Kagan, I think it's important to take into account the size, the sheer size, of this aquifer.

Not only does it encompass parts of eight -- it lies underneath parts of eight different states, but the thickness of the aquifer is huge.

In parts of it, it's as much as 500 feet.

In parts under Tennessee, it goes to 1100 feet. And so one inch of movement per day, which is what the testimony was at trial, can translate into tens of millions of gallons of water per day.

And, of course, if you were to annualize that, you'd be able to cover the entire District of Columbia in more than a foot of water by the amount that is moving one inch at a time out of this aquifer.

Neil Gorsuch: Mr. Frederick, our Doctrine of Equitable Apportionment arises in the area of moving water, of rivers, and you're asking to extend it to groundwater, and you've made a very strong argument for why that might be sound. I'm -- I'm wondering what the limiting principle is, however, and what we're buying here.

Is every aquifer in -- in the country that might have some interstate effect now going to be part of this Court's original jurisdiction? Is -- is Justice Breyer's fog now part of the Court's original jurisdiction? Is the Chief Justice's herd of wild burros, who may or may not be a nuisance, part of this Court's original jurisdiction now?

David C. Frederick: Well, what the Court has held is that the Equitable Apportionment Doctrine applies to natural resources, principally water and, in the one case of the fish, to the public trust doctrine.

Neil Gorsuch: But -- but so far --

David C. Frederick: And --

Neil Gorsuch: -- it has been about moving water and the fish.

You're right.

I forgot about the fish.

Okay.

But that's part of the moving water, the salmon in the river. And this is an extension.

And I'm -- I'm -- just analytically, what are the outer bounds of it? You can sell me on how it's not a big deal. Fine, I got it.

But what are the outer bounds of this principle?

David C. Frederick: I think --

Neil Gorsuch: Where does it end?

David C. Frederick: I think the outer bounds are where this Court recognizes the public trust doctrine to apply.

In those resources that are outside the public trust doctrine, the Court has not applied the equitable apportionment principle.

And so, in those -- in those resources -- air is one of them.

Justice Holmes recognized that in the old Illinois Central case over --

Neil Gorsuch: Right.

David C. Frederick: -- a century ago.

Neil Gorsuch: Right.

David C. Frederick: So, to Justice Breyer, you know, if there were --

Neil Gorsuch: So the wild --

David C. Frederick: -- such a plane --

Neil Gorsuch: -- the wildfires --

David C. Frederick: -- the fog actually --

Neil Gorsuch: -- in California affecting Colorado, the burros -- I'm not aware of any in Mississippi, but there might be some, wild -- all of that's now part of the Court's original jurisdiction?

David C. Frederick: Well, I -- I would say that, of course, the burden on the complaining state has to be a significant injury of substantial magnitude.

That has been the Court's standard for over a century from Kansas versus Colorado.

And if the burros or the fog created a significant injury of substantial magnitude, I think it would be appropriate for the Court to exercise its jurisdiction. Sitting here today, I have a hard time seeing that in the real world.

But I think that what the Court could say is that you have extended groundwater in certain respects to equitable apportionment cases when there has been substantial pumping of groundwater that has affected surface flows. You did that in the Oregon versus Washington case back in the 1930s, where there were 300 pumps of water on the Oregon side of the boundary, and the Court said that Washington nonetheless could show no injury to its own irrigators because there was subsur- -- subsurface flow that was occurring. You've held that in other cases involving compacts, where you've enforced compact decrees for surface flows notwithstanding the fact that there have been substantial water pumping going on on either side of the state. And so I think that it's not that far of an extension to say that where Mississippi has uniquely pleaded a claim about an aquifer that all the evidence showed at trial was connected to surface streams, and, here, the Wolf River, itself an interstate river, flows directly into the Middle Claiborne Aquifer at a recharge zone in the eastern part of the area that we're talking about.

Stephen G. Breyer: I'm still nervous about the question that Justice Gorsuch is asking.

I mean, there's groundwater under every state.

I mean, every state will start suing each other, except maybe Hawaii or Alaska.

And we haven't seen a lot of cases like that. And my -- my thought then is what you think about is maybe it could be done, but maybe it's better left to compacts or to Congress. And should we say anything about amendment? That's where the -- that's where we have to decide something here, because anything we say, of course, they have a right to ask to amend.

David C. Frederick: Yes.

Stephen G. Breyer: But, if we say a word about it, that's going to be taken as this is a totally appropriate kind of suit, and wild horses we worry about later, and -- and I don't know where it's going.

David C. Frederick: Well, Justice Breyer, two points in response to your question. One, I think their approach spawns much more litigation than our approach. Equitable apportionment is about sharing.

It's about sharing scarce resources when those resources become scarce.

It's not about money grabs because of the way that flow has been affected by pumping. And, Chief Justice, you asked about Tennessee counterclaims.

Dr. Waldron testified that there was significant -- tens of millions of -- of gallons of water every day that was flowing into Tennessee and out of Tennessee and into Memphis and -- and into Mississippi. And so what the evidence at trial would show would be that there would be substantial counterclaims if that were the standard.

And that's why we respectfully suggest it should not be the standard. Now, with respect to the fact that aquifers are under many, many states, in fact, most of the states in the country, respectfully, the question ought to be is there scarcity and, if there is scarcity, is there a doctrine that calls for conservation, calls for historic uses, calls for weighing the harms and benefits, calls for prospective action that would enable the scarce resource to be shared? And the answer is yes.

Stephen G. Breyer: Well, maybe we should just wait to decide that matter, which could lead to all kinds of lawsuits, until we have to decide it.

David C. Frederick: You could, but what I think you should say is that this is indisputably an interstate water resource in which there is flow.

If there is a remedy, it falls under the Equitable Apportionment Doctrine.

Mississippi has disclaimed an equitable apportionment claim.

Therefore, its complaint should be dismissed.

Period.

Amy Coney Barrett: And not specify with or without prejudice for leave to amend?

David C. Frederick: I don't --

Amy Coney Barrett: Just say nothing?

David C. Frederick: I -- I thought I just captured what I think is the appropriate disposition.

They haven't moved to amend their complaint.

They've been very careful not to say whether they plan to do it.

Their entire gambit here has been to get Tennessee to pay them hundreds of millions of dollars for water that in part they have intercepted at the boundary. So it's not -- and they say this on page 36 of the blue brief.

They do not claim that Tennessee is taking out more than its fair share of the water.

That's not their claim. Their claim is that they think they have an ownership right that entitles them to charge Tennessee for water.

And that, we think, the Court should say, no, that's not the correct statement of the law.

Brett M. Kavanaugh: Shouldn't a dismissal be without prejudice to them filing an equitable apportionment action? It would seem extreme to me to bar them from doing so in the future.

David C. Frederick: Justice Kavanaugh, I think that the correct disposition would be to dismiss this complaint, their territorial ownership claim, with prejudice.

And I would urge the Court to do that to disincentivize any other state from seeking --

Brett M. Kavanaugh: What -- what --

David C. Frederick: -- to limit a --

Brett M. Kavanaugh: Sorry to interrupt.

What would the effects of that be on their ability to file an equitable apportionment claim even if they can't show a material change in circumstances?

David C. Frederick: You would address that at the motion for leave to file a new complaint, where they would be put to their burden to show that there's been a material change and there has been a significant injury of serious magnitude, and Tennessee would respond depending on what they pleaded in their new complaint.

John G. Roberts, Jr.: Mr. Frederick, thank you.

I've had a little trouble following the science here.

Is this really water we're talking about? I mean --

David C. Frederick: Yes.

John G. Roberts, Jr.: -- it's complete -- well, it's mixed up with silt and small particles and all.

If you -- you can put it in your hand, right, and it would be silt? It would be wet, but, until you pump it, it's really not the water, right?

David C. Frederick: No, the definition of an aquifer is a fully saturated formation, hydrogeological formation, in which there are usable quantities of water.

John G. Roberts, Jr.: Yeah, yeah, I read that, but "fully saturated" means it's saturating something, right?

David C. Frederick: Yes.

It's sand mostly.

John G. Roberts, Jr.: It's not like a -- sand, okay.

Someone explained to me it's like you're in the -- the side of the shore and you put your foot down and when you lift it up, it kind of fills with water in that gap, right?

David C. Frederick: That is descriptive of parts of the aquifer, yes.

John G. Roberts, Jr.: Well, it's the part that I could understand. (Laughter.)

John G. Roberts, Jr.: So -- so why should we view it as like -- just like our interstate water cases? I mean, it is an unnatural operation of the pumping, separates out the water, and at that point, it's -- it's usable.

David C. Frederick: For the --

John G. Roberts, Jr.: But, before that, you would just call it silt, and if somebody showed you, you know, a handful of silt, they wouldn't say, oh, that's water.

David C. Frederick: Well, Mr. Chief Justice, I think you would say that it is water because it's some of the finest water that anyone can drink in the United States.

This artesian water is absolutely spectacular water that they have pumped, and they have run it over filters that filter out some of the iron and some of the other minerals, but it is very pure water and it is delicious. And I would urge the Court to consider the aquifer -- just because it is -- it is mixed in with sediment does not distinguish what it actually is, which is water when it is pulled out, and it is not a sophisticated scientific operation to do that.

John G. Roberts, Jr.: Thank you, counsel. Justice Thomas?

Clarence Thomas: No questions, Chief.

John G. Roberts, Jr.: Justice Breyer?

Stephen G. Breyer: No.

John G. Roberts, Jr.: Justice Alito? No?

Neil Gorsuch: Mr. Frederick, on the -- on -- on the question of leave to amend, just to nail that down, would -- would you have any objection to this Court simply resolving the case as before us and saying that there is no leave to amend currently pending before us? We don't need to address it.

The Special Master was erroneous to the extent that he suggested there was?

David C. Frederick: We -- that if -- with that last part, Justice Gorsuch, we would have no objection to that.

Neil Gorsuch: Okay.

John G. Roberts, Jr.: Justice Kavanaugh?

Brett M. Kavanaugh: No further questions.

John G. Roberts, Jr.: Justice Barrett?

Amy Coney Barrett: I do have one question following up on the Chief's question to you about separating the water from the silt. What if you could separate out some other thing from the silt, like some sort of mineral, and find some sort of way to pump it and pull it into Tennessee? How would that fare? Would that be subject to equitable apportionment?

David C. Frederick: No, Your Honor. Minerals have not been subjected to the Equitable Apportionment Doctrine because they're not covered by public trust.

They are privately owned, usually through surface ownership rights by personal property.

Sometimes they get severed in some states where you can own the surface land and sever off the mineral rights. Those would be treated separately under well-established law.

Amy Coney Barrett: Thank you.

John G. Roberts, Jr.: Thank you, counsel.

David C. Frederick: Thank you.

John G. Roberts, Jr.: Mr. Liu.

Frederick Liu: Thank you, Mr. Chief Justice, and may it please the Court: Under Mississippi's theory of this case, certain groundwater belongs to Mississippi simply by virtue of having passed through Mississippi's territory. There's no support for such a theory. Indeed, Mississippi can't point to a single jurisdiction that has ever allocated groundwater based on such a theory. This Court, when confronted with disputes over the allocation of interstate resources, has applied the Doctrine of Equitable Apportionment.

That doctrine represents the most sensible way of allocating an interstate resource because it respects the equal sovereignty of the states. And Mississippi identifies no reason why that doctrine should govern interstate surface water and fish but not the groundwater at issue here.

Mississippi's exceptions to the Special Master's report should, therefore, be overruled. I welcome the Court -- the Court's questions.

John G. Roberts, Jr.: Well, counsel, you say on page 18 of your brief that Mississippi's case is indistinguishable from -- from or at least sufficiently similar to all the Court's prior precedents because it's groundwater that -- it crosses across state lines and affects the other state. But there are a lot of other ways in which it's distinguishable.

The fact that we were just talking about that it's -- however delicious it might be when you get the silt out of it, it's not too good when the silt's in it and the fact that it's groundwater. And I'm just wondering, this is a case of first impression, isn't it? You really are trying to move this beyond the flowing water and the fish?

Frederick Liu: Well, it -- it's true that this Court has not addressed directly the question of how to deal with the allocation of water in an aquifer.

Our point is that this Court's prior precedents have identified two characteristics of the resources at issues in those cases that justified the application of the Doctrine of Equitable Apportionment. And in this case, those two characteristics, that is, the resource moving naturally across state lines and the fact that one state's use of the resource within its borders affects the presence of the resource in the other, those two characteristics are present here.

At least they're sufficiently similar. And so, while there are certainly differences between groundwater and surface water, those are the -- those are the two differences that matter, and they matter because, when those characteristics are satisfied, that's when the Doctrine of Equitable Apportionment makes sense. When those characteristics exist, you're inevitably going to have a conflict of sovereign interests of, on the one hand, the sovereign interest of the state's right to use the water here in Tennessee and, of course, the sovereign -- the interests of the other sovereign to protect its citizens from whatever effects that use may have. And because one state can't simply impose its policy on the other, the Doctrine of Equitable Apportionment does what the best we can do, which is to treat each state as an equal sovereign, take account of all their interests, put both states' bound -- both states' interests on the balance, and then reconcile them as best as we can.

Elena Kagan: Mr. Liu, suppose that instead of drilling their wells straight down, Tennessee drilled its wells, like, on a slant --

Frederick Liu: Right.

Elena Kagan: -- so that, in fact, the wells did cross the boundary between Tennessee and Mississippi.

Is it then an equitable apportionment claim, or, at that point, does Mississippi have a different kind of action?

Frederick Liu: Well, I want to be clear about what we think the domain of equitable apportionment is.

We think this doctrine applies when one state is complaining about the other state's use of the water. So there might still be equitable apportionment as --

Elena Kagan: Well, that's really what Tennessee -- Mississippi would be complaining about, right? Because it's drilled these wells and it's getting all this water. Let's say that the gravamen of the claim is really exactly the same, they're taking our water. This -- the only thing that's different --

Frederick Liu: Right.

Elena Kagan: -- is the mechanism, that the mechanism they've used is one that does a physical trespass.

Frederick Liu: Yeah, that -- that's definitely a different case.

And I think it's because the -- there's a -- an additional harm there that I think has been understood --

Elena Kagan: But not the harm that anybody cares about.

You know, it doesn't matter that it's stepped an inch onto Mississippi's land.

What -- you know, what Mississippi is complaining about is we have less water than we used to have.

Frederick Liu: Well, I -- I think it does matter whether the -- the state is crossing the boundary or not.

That -- that isn't -- that isn't a --

Elena Kagan: Well --

Frederick Liu: -- circumstance where --

Elena Kagan: -- presumably, that would be a very minimal kind of damages, this -- the crossing of the border.

The damages are going to come from the taking of the water, and the taking of the water, let's presume in my hypothetical, is exactly the same.

Frederick Liu: If the taking of the water is exactly the same, I think there -- the water would still be subject to equitable apportionment, but one very important factor in how you import -- apportion that water might be how the water was extracted. Again, I just want to be clear there probably is room for a different kind of tort that's actionable because of the trespass, and so I'm not saying that that's -- that's somehow, you know, not -- not as -- not an important boundary that's literally been crossed in that case. Now my friend tries to distinguish this Court's equitable apportionment cases from this case on a number of grounds, but I don't think any of those grounds suffices.

One of the things my friend said was: Well, in this case, we have an exercise of Mississippi's sovereign authority.

But, of course, that's going to be true in all of this Court's equitable apportionment cases.

There's always going to be, for example, an upstream state that's exercising sovereign authority over the water before it passes on to another state. My friend mentioned this unnatural effect of -- of -- of how the water is moving from Mississippi to Tennessee.

But, in all of these cases, what you're going to have is some human intervention that extracts the resource from its natural state, whether it's the fishermen in Idaho v. Oregon or the irrigators in Kansas versus Colorado.

Here, it's the wells in Tennessee.

So that -- that doesn't really distinguish this case. The mechanism by which the water is moving across, that's not different in this case either.

In all of these cases, the effect that one state has on the other, the mechanism is through the agency of natural laws. So, in the case of a stream, it's -- it's just simple laws of physics that if you take water out of a stream, there's going to be less water downstream. Here, it's really no different.

I mean, the -- the experts have put a fancy name on what a cone of depression is, but anyone who has ever removed water from a vessel knows that when you remove the water, more water is going to flow to where you removed it.

And -- and that's -- that's simply what's happening here. The one thing my friend also mentioned was the -- the pace of the movement.

But the fact that it's moving slowly doesn't change the fact that what we have here is a single continuous resource that moves across state lines. And, as Mr. Frederick emphasized, that movement is hardly trivial.

We're talking millions and millions of gallons per day. Compare that to the river at issue in Kansas versus Colorado.

There, the Court noted that the flow of the river varied during certain parts of the year and in even some parts of the year ran totally dry. And the Court said, well, that doesn't really matter.

What matters is that we're talking about a single continuous river that flows from Kansas to Colorado -- I'm sorry, from Colorado to Kansas.

And, here, we're talking about a single continuous aquifer that -- that exists underneath eight different states, including Mississippi and Tennessee. Justice Kavanaugh asked about the uncertainty that might exist if this Court adopted Tennessee and our view of the case.

I think it's -- it's quite the opposite, that the approach that Mississippi is advocating is unprecedented. This -- this might be a new issue, Mr. Chief Justice, that this Court is addressing, but the allocation of groundwater is an issue that's resolved intrastate every day of the week.

We -- we have state courts that look at, well, how do we allocate groundwater between one owner or the other? And the way they do it isn't the way Mississippi wants you to do it. No one -- no one pulls up water from a well and then says, well, some of this -- some of these molecules came under the landowner's property; I have to -- I have to put those back in the water.

No, all -- all these jurisdictions apply some sort of equitable principle where they share the water that's underneath them. So I think the upheaval would come not from adopting our approach, which is continuous with not only this Court's equitable apportionment precedents but also how states deal with this issue, but rather in adopting my friend from Mississippi's position.

Brett M. Kavanaugh: Mr. Liu?

Frederick Liu: Yes.

Brett M. Kavanaugh: The final sentence of your brief says that the complaint should be dismissed.

Should that dismissal be with prejudice or without prejudice?

Frederick Liu: Well, Justice Kavanaugh, we did not file an amicus brief on Tennessee's exceptions to that part of the Special Master's report, and so we don't take any position on that issue.

We view that as principally a dispute between these specific parties. I will say, though, that Mississippi has gotten a number of chances already to seek an equitable apportionment claim.

They -- they filed a complaint in 2009.

They filed the instant complaint in 2014.

In neither complaint have they made any real effort to plead an equitable apportionment claim. And so we would simply ask this Court that if it does allow leave to amend in this instance that it at least allow those new allegations to be subject and tested to a prompt motion to dismiss or motion for judgment of the plead -- on the pleadings just in case we don't need any lengthy discovery or an evidentiary hearing to -- to resolve what --

Brett M. Kavanaugh: Well, they -- they presumably didn't raise that because they didn't think that was the right box, analytical box, for this kind of dispute.

But, if we say that, in fact, equitable apportionment is the right categorization, why should they be precluded from then seeking an equitable apportionment remedy as a matter of basic fairness?

Frederick Liu: I -- I think whether this Court gives them a chance to seek that opportunity, basically, it comes down to whether this Court thinks enough is enough or whether they've already had a chance to do so.

We don't have a position on whether Mississippi is given that opportunity. Our only point is that if they are given that opportunity, that we -- we -- that this Court allow those allegations to be tested promptly because, at least so far, the allegations we've seen with respect to injury, which is a threshold requirement of equitable apportionment, haven't -- haven't been sufficient. Justice Gorsuch mentioned a concern about opening the doors of this Court's original jurisdiction.

I think one of the -- one of the underpinnings of this Court's original jurisdiction docket has been this threshold requirement of injury.

This Court has -- has consistently required that the complaining state show an injury of serious magnitude that would justify invoking this Court's extraordinary authority to compel one sovereign to -- to stop what it's doing. And I -- I -- I think here, again, our proposal would leave that injury requirement in place.

And so that injury requirement would filter out many of the cases that simply don't have merit. I think another problem with Mississippi's approach is that they have no injury requirement.

Mississippi has not really tried to show injury here.

They've simply tried to show that certain molecules took a certain path through the water from Mississippi to Tennessee.

And every state that sits on top of an interstate aquifer and that drills wells is going to inevitably create a cone of depression and you're going to have these claims available to this --

Neil Gorsuch: But -- but why doesn't that suffice to state a harm in -- in at least an Article III type sense, that the less water available to Mississippi necessarily impairs its natural resources and, therefore, its ability to attract businesses and residential units in the future, and maybe it doesn't need it today, but it's -- it's in the bank for -- for the state's future and future generations?

Frederick Liu: Well, we -- we're certainly not challenging Mississippi's Article III standing in this case.

Neil Gorsuch: Yeah, but you're saying an -- an injury.

So why isn't that an injury? Or just an injury in the sense of -- of the aesthetic pleasure of knowing and certainty that your natural resources are preserved for future generations?

Frederick Liu: And -- and -- and I think, Justice Gorsuch, when this Court is properly presented with an equitable apportionment claim, the Court would have the opportunity to discuss what sorts of injuries in this context suffice.

Neil Gorsuch: You're selling us on injury as being a filtering device, no pun intended, right?

Frederick Liu: No pun intended.

Neil Gorsuch: No pun intended. But -- but -- but now you're saying that that will have to be sorted out in the future.

Is that what I'm hearing?

Frederick Liu: Well, I think, at -- at a minimum, the injury can't be a injury to their right of ownership or sovereign control over the --

Neil Gorsuch: But if -- I -- I --

Frederick Liu: -- resources.

Neil Gorsuch: Again, I can just -- I can transplant that.

Instead of ownership, if you don't like ownership, how about parens patriae and the protection of natural resources for future generations? Do you like that?

Frederick Liu: Well, I think they could get in the door, but then the question is whether --

Neil Gorsuch: That gets them in the door, but ownership doesn't?

Frederick Liu: Ownership doesn't because that -- that's -- that's -- that's simply a legal right that doesn't exist.

And I think even today Mississippi conceded that they're not claiming absolute ownership over this resource. Their -- their point in invoking sovereign authority in ownership is to sort of justify a legal theory that -- that -- that would in turn justify the 615 million dollars in damages they're seeking. And my only point is it didn't take much for them to be able to allege that claim, and it's not going to take much for other states either because these cones of depression are the inevitable consequence of any well use over an interstate aquifer. And there's nothing stopping Tennessee, if Mississippi's theory is upheld, from bringing the very next suit.

So --

Neil Gorsuch: So it sounds to me like the government thinks that it should be equitable apportionment because that's a better doctrinal fit but that Mississippi very likely has a claim it can state?

Frederick Liu: I -- I -- I -- I doubt that Mississippi has a claim it -- it can state.

If you look at our limitation brief that we filed when -- when -- when -- when Mississippi originally filed the complaint, we looked at the allegations and said in that brief that the allegations were not sufficient enough to -- to plead a sufficiently serious injury. Now it may well be that Mississippi has injuries now they would like to plead. Granted, they weren't trying to plead an equitable apportionment claim in 2014.

But the allegations we've seen have not sufficed.

John G. Roberts, Jr.: Thank you, counsel. Justice Thomas?

Clarence Thomas: No questions, Chief.

John G. Roberts, Jr.: Justice Breyer? Justice Alito? Justice Kavanaugh, any further questions?

Brett M. Kavanaugh: No further questions.

John G. Roberts, Jr.: And Justice Barrett? No? Thank you, counsel. Mr. Frederick, you have rebuttal? I'm sorry, Mr. Coghlan, do you have rebuttal? Thank you.

John V. Coghlan: Thank you, Mr. Chief Justice.

Just -- just briefly a few points. On the suggestion that Mississippi does not have the ability to -- to show a real and substantial injury, we -- we certainly dispute that. And the core injury which we pled from the beginning, I think, is an injury to Mississippi's sovereignty.

That's the -- the core injury, the fact that Tennessee is acting extraterritorially and usurping Mississippi's exclusive sovereign control over the groundwater within its borders.

We think that in of itself is a -- a sufficient injury, as recognized in -- in Tarrant. But we have others.

It's certainly the case that Mississippi's -- the cost of Mississippi to access the groundwater has increased.

Dr. Sprule, Mississippi's expert, talks about this in the hearing transcript at pages 212 to 214, that there's greater cost because the water levels have dropped as a result of this pumping.

So, while they may in theory be able to get the same amount of water, as Mr. Frederick said, that comes at a greater cost. More importantly, there's a suggestion that there's no indication that there's any harm to the water.

The record evidence suggests otherwise too.

Defendants acknowledge at page -- or, excuse me, Defense Finding of Fact 156 that their pumping is draining an overlying surficial aquifer, and both the U.S. Geological Survey and Mississippi's expert, Dr. Sprule, have testified that that's pulling contaminants down into the aquifer at issue here, which is where both states get their drinking water from. So we think that's a real and substantial injury.

And these issues have not fully been explored.

Because of the way the Special Master set up the proceedings, Mississippi did not have a chance to fully build a record on this -- on these points, but we do think that there's sufficient evidence there. Justice Kagan, you asked whether the case would be different if some of these wells physically intruded by an inch in -- across the border.

And I think your question demonstrates why that shouldn't matter, because even if it is an inch, but all the damage and the injuries that -- is the same, it really kind of elevates form over -- over -- over substance. And I turn back to Tarrant.

Tarrant did not talk about there being a physical violation or invasion of space.

Tarrant talked about a proposed diversion of water and exercising control over the water in that case. And I think that's where the injury was considered there, and that's where the injury is here, that Tennessee is exercising control over groundwater while it was within Mississippi. And just -- just finally, if the Court, you know, wants to consider applying equitable apportionment to groundwater, which we don't think it needs to answer that question to rule in Mississippi's favor, I would contend it doesn't solve the problem because of the nature of groundwater. Extracting groundwater has a very limited area of effect, so you can't just apportion it and say each state gets a certain amount of water.

Tennessee gets 5 billion gallons and Mississippi gets 5 billion gallons. Where that water is coming from and specifically with relation to the border matters because Tennessee, as we've said, could get all the groundwater it wants, could pump as much as it wants, and have no impact whatsoever on the Mississippi because of the nature of groundwater. So I think simply apportioning it without taking into consideration the border will not solve the problem.

And that's why we contend that's what the -- this is a different injury and -- and -- and requires a different remedy. And so, ultimately, we think Tarrant addresses the case that we have here.

We don't think the Court needs to pave a new -- new law to -- to rule in Mississippi's favor.

We believe they just need to extend the principles recognized in Tarrant to the case here. Thank you.

John G. Roberts, Jr.: Thank you, counsel.

The case is submitted.