The Endangerment Finding and the Future of EPA’s Authority

On February 12, the U.S. Environmental Protection Agency formally rescinded the endangerment finding, the 2009 determination that established the legal basis for federal regulation of greenhouse gas emissions. For 16 years, that finding has underpinned EPA climate policy, reflecting the agency’s conclusion that greenhouse gases pose a threat to human health and that, under the law, it was required to regulate them.

The move represents a major shift in federal climate policy. But agencies cannot simply reverse themselves without making a legal case that can withstand court review. Cary Coglianese of the University of Pennsylvania Carey Law School and Shelley Welton of the Kleinman Center and Penn Carey Law examine the legal rationale behind the rescission and how it draws on recent Supreme Court decisions that have narrowed federal agency authority.

Rather than disputing climate science, the EPA’s argument rests on a more limited reading of its powers under the Clean Air Act. Welton and Coglianese explain how that argument fits within the Court’s evolving approach to administrative power, and what it could mean for the future of federal climate regulation.

Full Transcript

Andy Stone: Welcome to the Energy Policy Now podcast from the Kleinman Center for Energy Policy at the University of Pennsylvania. I’m Andy Stone.

On February the 12th, the US Environmental Protection Agency announced that it had formally rescinded the endangerment finding, the 2009 determination that formed the legal basis for its regulation of greenhouse gas emissions. The 16-year-old endangerment finding was, in a nutshell, EPA’s determination that greenhouse gasses are harmful to human health. Under law, the agency was therefore required to regulate them. But federal agencies, the EPA included, can’t simply do an about face on their own past decisions. Today’s EPA needed to develop a strategy that would allow them to nullify that prior determination in a way that could withstand legal challenges that in all likelihood will rise to the Supreme Court.

On today’s podcast, we’re going to be taking a look at the legal strategy the EPA has employed to roll back the endangerment finding, a strategy that, at least on its face, does not directly challenge climate science. Instead, the EPA’s justification rests on a much more limited interpretation of its own obligation to regulate greenhouse gasses, making this an argument about what the agency is permitted by law to actually do.

My guests are two legal experts who will describe the EPA’s move and the history of legal precedents and recent rulings that may determine its fate. They’ll also consider whether climate science can truly be separated from the questions at stake, and offer their perspectives on how durable the EPA arguments may be. Cary Coglianese is Director of the Penn Program on Regulation at the University of Pennsylvania Carey Law School. Shelley Welton is Presidential Distinguished Professor of Law and Energy Policy with the Kleinman Center and Penn Carey Law. Shelley and Cary, welcome to the podcast.

Shelley Welton: Thanks, Andy.

Cary Coglianese: Great to be here.

Stone: So Shelley, let’s start with you. I’d like to clearly define what the EPA has actually done, which has been widely described as overturning or repealing or rolling back the endangerment finding. But the terminology here is important, and the term is rescission. So Shelley, what does this mean? And again, precisely, what has the EPA done?

Welton: Yeah. So, they call it a rescission, and I think you can understand that basically as saying they’re taking back their finding from 2009 under the Clean Air Act that greenhouse gasses endanger human health and welfare. And basically what they’re saying is, the line of reasoning they’ve put forward is that they never had the legal authority to make such a finding in the first place. And I think this is a significant distinction, because what they’re basically saying— and I think we’ll get into this more— is that means we don’t think we ever had the legal authority to issue the many regulations that flowed from the endangerment finding, and they should essentially all be defunct now, is the EPA position.

Stone: So the endangerment finding has, as I mentioned, been heavily covered in the news. But I think it’s also, at this point, worth it just to take a moment to briefly review exactly what the 2009 finding was, as well as the 2007 Supreme Court case that led to it. So Cary, can you give us a brief background here before we dive into what we’re going to be talking about today, which is the EPA recent action?

Coglianese: Well, the history here actually goes back to the late 1990s, believe it or not, to the Clinton Administration, when the EPA General Counsel — actually a former Penn Law School alum, Jon Cannon — issued a memo asserting that the Clean Air Act gave the agency authority to regulate greenhouse gas emissions. The EPA didn’t do anything with that authority, or that asserted authority, in the 1990s. But what it did prompt were petitions for the agency to engage in greenhouse gas emissions that were then ruled on during the second Bush administration. And that administration actually flip-flopped, changed course, and said, “You know what? Not withstanding that prior year legal memo that was adopted in the Clinton Administration, we now no longer think we have the authority to regulate greenhouse gasses under the Clean Air Act. And for that reason, mainly, we are going to deny these petitions to adopt any rulemaking on greenhouse gasses.”

That went into the courts to challenge that denial of that petition. Ends up, in 2007, in front of the Supreme Court. And the Supreme Court, in a five to four ruling, roundly rejects the Bush Administration’s position that they lacked authority under the Clean Air Act to regulate greenhouse gasses, finding that greenhouse gasses met the statutory definition of air pollutants. And so therefore it was incumbent upon the EPA to decide whether greenhouse gasses were air pollutants that endanger the public. And if so, then that would trigger an obligation to to regulate.

And so in 2009 now, we’re in another administration altogether, the Obama Administration. The EPA adopts an endangerment finding under the title two of the Clean Air Act which deals with motor vehicle emissions, and says that for purposes of this title, we are deciding that greenhouse gasses— six greenhouse gasses in particular, including carbon dioxide — are ones that threaten public health and well being. And therefore we need to adopt motor vehicle emission standards.

And since that time, the agency has issued other climate change regulations, a few of them dealing with stationary sources — that is, factories, smokestacks coming from buildings and not exhaust pipes coming from cars or mobile sources.

And now, of course, we’re back to, in some sense, the future flipping back, or maybe it’s Groundhog Day that’s the better movie analogy. We’re seeing the EPA resurrect, essentially, that the argument that had been put forward by the Bush Administration and that had been rejected by that five to four majority in Massachusetts versus EPA, that the Clean Air Act was not intended to address greenhouse gas emissions. That it just is a statute addressing local and regional air pollutants. And therefore, notwithstanding all that we’ve done over the last decade and a half with respect to greenhouse gasses, we really can’t do that.

And so at the same time as they have rescinded this endangerment finding, they have also rescinded the more stringent greenhouse gas emission standards with respect to automobiles that have been in place for a while. It should be noted, by the way, just by way of giving a background here, that when it comes to regulating greenhouse gas emissions from automobiles, the results are really not much different than regulating fuel economy, which is a set of standards that that can be adopted and are adopted by the Department of Transportation and its National Highway Traffic Safety Administration. And so because greenhouse gas emissions — carbon dioxide in particular — is really a function of burning of fossil fuels, the more fuel efficient you make cars, the fewer greenhouse gas emissions. So it should be noted that at the same time that the EPA has eliminated its endangerment finding and eliminated its greenhouse gas emission standards for automobiles, the Department of Transportation has also proposed to roll back and weaken, if you will, the CAFÉ, or fuel economy standards for automobiles.

Stone: So the EPA regulates carbon dioxide emissions, but the Department of Transportation regulated the fuel economy that resulted in the carbon dioxide emission. So it was kind of like those two agencies almost working together under the Obama administration to ultimately limit the amount of carbon dioxide or greenhouse gas emissions from vehicles.

Coglianese: Right. In the past, they have coordinated their regulatory efforts.

Stone: I want to just make one other point clear, and I’m going to turn this one to you, Shelley. Just before we go any further again, if the EPA determines that a pollutant endangers public health, and it had done that with a group of six greenhouse gasses in 2009. Is it required to regulate those pollutants, or does it retain some discretion to regulate or not?

Welton: You’re asking a complicated question. And I guess what I’ll say is that once EPA made this endangerment finding, some things immediately happened. And some, the agency still had some discretion or judgment to exercise about what to do. So I think Cary gave a really nice overview of Massachusetts versus EPA. It mostly was about this question of whether or not greenhouse gasses are an air pollutant.

There was a second piece of the case where the Bush Administration basically made two arguments in Mass v EPA. Argument one was, we can’t regulate greenhouse gasses because they’re not pollutants under the act. Cary already explained how the Supreme Court said no. The second argument that they made was that the specific section that deals with motor vehicles, section 202 — they argued that because the section said that there was a judgment to be made by the administrator about whether or not these endangered public health and welfare, it was okay for the administrator to say, even if they do endanger public health and welfare, we prefer not to regulate them right now. And the administrator had basically said, “This interferes with geopolitics. We don’t think it would be wise to do this. We have other strategies. Congress has said they don’t want to.”

And what the Supreme Court there said is, once you’ve decided that something is a pollutant, the only reasons that you can decide under Section 202 not to regulate are that it actually does not endanger public health and welfare. You can’t say, “For other policy reasons, we just decline,” right? So there essentially was something like a mandatory obligation to make an endangerment finding based on the science, which is what EPA did in 2009. Once that happened, I like to think of the section 202 endangerment finding as the key that unlocked the door of the Clean Air Act for climate change.

So once that happened, some things kind of automatically followed from it, like stationary sources that were already being regulated for other pollutants then automatically became regulated for greenhouse gasses. There’s some parts of the act, though, which ask the administrator to again exercise their judgment about whether or not to regulate a pollutant under that section. So for example, section 111, which has been the big section used to regulate power plants, has a similar sort of finding that the administrator has to make, that power plants cause or contribute significantly to air pollution that endangers public health and welfare as well. And so you’ve seen these sections be discretionarily adopted by administrators to push regulation into other sources, but all stemming from the section 202 endangerment finding.

Stone: So let’s jump now to where we are right now in early 2026. So, the EPA has moved to decisively repeal the legal foundation for greenhouse gas regulation at the federal level. And the EPA had two possible routes to accomplish this. One, attack the climate science directly. And two, have the agency challenge its own authority to regulate greenhouse gasses — which you’ve both already started to introduce. And that’s a legal rather than a scientific question. So Shelley, can you tell us why has the EPA taken the second route?

Welton: I think, fundamentally, because the science on climate change is extraordinarily well established. There’s pretty much near scientific consensus on the nature and the scope of the problem, and the science has only gotten stronger since the endangerment finding amassed a huge amount of evidence that greenhouse gasses do, in fact, endanger public health and welfare.

And so, you know, I think ultimately, although this EPA thought about and proposed in its notice of proposed rulemaking a separate basis for the endangerment finding — that is that the climate science has uncovered new uncertainties, and it’s not clear that endangerment is present — they got such tremendous pushback on this. And I think when they thought about the risks of essentially having to go to court and try to litigate that climate science is almost universally wrong, I think they just decided that that was probably not a tenable basis on which to try to revoke the endangerment binding. Or at least not one that they they wanted to undertake the effort of trying to defend in court. And so, as you said, they went with a much more legalistic route for rescinding the finding.

Stone: And there’s something — I’m not the lawyer here — but there’s something known as the Administrative Procedure Act, that really says that any agency really has to back up any decision they make, right? And that that plays into this as well.

Coglianese: The Administrative Procedure Act also says that when an agency wants to repeal or rescind an earlier rulemaking, it has to go through the same rulemaking process. And the courts have construed the judicial review provisions of the Administrative Procedure Act— which may or may not apply exactly to the Clean Air Act, because the Clean Air Act has some of its own judicial review provisions. But I think the courts tend to follow the same judicial review standards, the language is in certain respects quite similar. But they would be looking for the administration on a repeal to demonstrate that their actions are not arbitrary and capricious, to the same way that they would be asking for that demonstration if it were the case that the agency were putting the rule in place in the first instance.

The test is, in theory, the courts have said the same — whether you’re rescinding a rule or putting a rule in place in the first instance, that you’ve got to show the evidence. Consider all the alternatives. You know, really make a case on the facts, the science, the policy analysis. That’s something that is intrinsically harder to do when you are rescinding any regulation. Why? Because a prior administration has presumably put forward a lot of facts, evidence and policy analysis supporting the adoption of that rule in the first instance.

So everything that Shelley mentioned is absolutely right and valid. It’s even a more general kind of concern that in some ways, it’s easier to kind of kneecap the agency on legal grounds. In which case, you don’t have to worry at all, essentially, about all this stuff, about the science and facts. Because if the agency just lacks the legal authority, then it doesn’t matter how important the rule was from a social welfare standpoint, it doesn’t matter how well justified it was on policy or scientific grounds.

Stone: Let me ask you this. Is this just something that comes to mind — is there a precedent for an agency seeking to actively reduce or rein in its own authority? Do agencies normally do that?

Coglianese: Well, I mean, Massachusetts versus EPA was precisely such a case in which the agency flip flopped. It was initially claiming it had the authority to regulate greenhouse gasses, and then the new administration comes in and says, “No, we don’t.” This is like — elections matter, right? And so the different postures of administrations will make a difference here.

Welton: More broadly, I think the public choice movement of the ‘60s and ‘70s often had this theory that an agency will only ever seek to accrue authority and gain more authority. But I actually think that during the broad deregulatory moves of the ‘80s and ‘90s, you saw lots of agencies that were willing to relinquish authority because they believed, for ideological, practical reasons, that it would be better to have less regulation. And so, you know, I don’t think that this is a totally new move. Although I do — and we can get to this — think the bases here are far more tenuous than many of those earlier efforts.

Stone: So let’s get into those bases here. And I want to direct this one back to you, Cary. So the potential for success of the EPA legal strategy here, and its ability to withstand legal challenges, might be changed or potentially improved. By the way, the legal environment generally has changed since Mass versus EPA back in 2007. So there have been some changes. There have been some court cases that create a new context. Could you talk about what has changed, Cary, and how potentially might that make the EPA rescission more likely to succeed today?

Coglianese: Well, one thing that’s changed are just the numbers. Massachusetts versus EPA was a five to four decision. None of the members of the majority — none of those five members that voted in favor of the outcome that EPA has the authority under the Clean Air Act to regulate greenhouse gasses — none of those justices are on the court today. Out of the four dissenters in Massachusetts versus EPA, three of them remain on the court. So if you’re just looking at the numbers, changed circumstance.

Stone: That’s quite a lot of continuity.

Coglianese: Yes. And then the question is, what is the likelihood that there will be two votes from some of the two members that were not on the court? The conservative members that could come on who weren’t on the court at that time. Will they adhere to precedent and uphold Massachusetts versus EPA—  a decision, by the way, that — yes, it was five to four. But it, in subsequent cases, was essentially affirmed. Chief Justice Roberts, for example, was a dissenter in Massachusetts versus EPA. But he joined the court’s opinion in a case called American Electric Power v Connecticut in 2011, a case involving the ability for other kinds of collateral litigation to go forward to try to address climate change, in which the Court said that litigation is foreclosed. Why? Because EPA has the authority under the Clean Air Act to regulate climate change and to deal with climate change. And the very beginning of that opinion in the Connecticut case says “Massachusetts versus EPA.”

So Roberts has gone along with precedents in the intervening years that are premised on the EPA having this authority. We’ll have to see whether he’s now willing to reconsider. And one of the other things we’ve seen with this court in recent years is a willingness to retreat from well- established precedents, whether it was Roe versus Wade or whether it was the Chevron doctrine, which the Court has said it has overruled.

And I guess that’s where you want to really ask about, what have some of the doctrinal changes been since Massachusetts versus EPA? I mean, one doctrinal change has been at least a purported overruling of the Chevron doctrine. This was a doctrine that was in existence at the time of Massachusetts versus EPA. Not clear that it really made a difference to the majority, although it did, interestingly enough, figure into the dissent that Scalia authored and Roberts joined in that case, that the Chevron doctrine gave agencies permission to construe an ambiguous statute in various ways, as long as it was reasonable.

And the court, in the decision of Loper Bright Enterprises a couple of years ago, says it overruled Chevron. Although when you read the opinion closely, it’s not clear whether it really did much to change, doctrinally, the way courts are supposed to approach cases where an agency has interpreted a statute. In the Loper Bright decision, there’s provisions that say that we recognize that Congress sometimes can delegate authority to agencies to construe ambiguous statutes. And we could even look for express language about that.

And so Shelley mentioned earlier, some of the language in the Clean Air Act about giving the EPA administrator a judgment call might be construed as a kind of delegation that would be permissible under Loper Bright, just as it was permissible under Chevron. And Justice Scalia was accepting in his dissent in Massachusetts versus EPA. So the Loper Bright decision in the purported overruling of Chevron is not so clear cut.

Another case, though, West Virginia versus EPA, which was a key case challenging an EPA climate regulation, the signature climate regulation that the agency had, the court rejected the agency’s authority to adopt that regulation, because it was raising a major question and had not been squarely and clearly resolved by the statute whether the agency had authority to deal with that big issue like climate change. The West Virginia case evinces, I think, clear skepticism by the Supreme Court toward significant policy decision-making by administrative agencies, significant regulatory decisions. So I think that case, combined with the shift in the court’s composition, probably does more to signal the likelihood — or maybe it’s 50-50, maybe it’s 75-25 — that the current court will uphold the Trump administration’s rescission of the endangerment finding.

One last little wrinkle here about change. And it’s really in the weeds, but the Inflation Reduction Act had some language added to the Clean Air Act that identified as air pollutants, greenhouse gasses. And that could figure in as a changed circumstance to how the legal analysis plays out. The point is, the Trump administration’s, I think, taking a gamble here. But it’s taking a gamble where, again, with the numbers at least, the odds seem to be not unreasonable that it will prevail.

Stone: And just to go back to that West Virginia versus EPA case in 2022, just to make that one clear. That was basically the nail in the coffin for the Clean Power Plan, which you did mention was the signature climate regulation covering the electricity power generation industry that had been put in place in 2015.

Coglianese: Yeah. And the court was — it’s been very clear that it didn’t like that regulation from the get-go. It made the unprecedented move of issuing a stay, and that is locking down and keeping that regulation from taking effect pending litigation, something that a court had never done. When the lower courts refused to issue such a stay, the Supreme Court stepped in and blocked the EPA from going forward. And then there were a number of, I think, legal gymnastics at stake even for the Court to hear the West Virginia case. But it it was clear that this was not something that was going to stand. And I think the Trump Administration, like I say, is maybe making a pretty good bet that they’ll ultimately prevail in the Supreme Court, when this gets there with the endangerment finding repeal.

Stone: So Shelley, I want to look at another element here. Given that the endangerment finding has been in place for over 15 years and it shaped regulation and investment decisions, how important are what are known as reliance interests here, meaning the way businesses and states have structured policies and investments around that framework?

Welton: I think they’re hugely important, especially as regards motor vehicles, which is the original endangerment finding’s core sector. And you know, I will also say that I think they’re quite politically interesting. You really didn’t see the auto industry clamoring for this rescission at all. They had quibbles with exactly how the Obama Administration and then the Biden Administration structured and set the timing for greenhouse gas regulations, but none of them were calling for a full-on abandonment of the endangerment finding, I think, because they really didn’t want the regulatory uncertainty that comes with what is certain to be years of litigation ahead.

And maybe just to even take a step back from that. One of the things that I’ve heard commentators mention about the position that this puts the US auto industry in is that we are — this puts us very out of step with the rest of the world, which is rapidly moving to electric vehicles. I saw a stat somewhere yesterday that in Norway last month, a total of seven gas-fired cars were sold.

Stone: Wow.

Welton: All month, in the entire country, right? So when you see a bunch of countries experiencing rapid electrification, with China clearly dominating the electric vehicle space, we may be sort of hoisting ourselves on our own petard by not having the sector keep up with the global marketplace domestically.

I think the reliance interests are less clear for other sources, like power plants. Because I mean, as Cary just walked us through, there’s been an epic battle about what to do with power plants under the act, and it’s flip flopped a lot over the years. So there hasn’t been the same sort of solid set of investments driven by those regulations. But you know, at the same time, all the economics is pushing away from coal towards natural gas and renewable energy anyway. And so I don’t think you saw a lot of interest from anyone, really, in the industry, in having the endangerment finding rollback be the way to halt climate action, as opposed to just attacking individual regulations that they didn’t like.

Stone: So, Cary, challenges are starting to line up to the EPA rescission. And one of the challenges that has been brought up so far is from a group that includes the American Lung Association, the Clean Air Council, the Natural Resource Defense Councils, and others that are in that group. And the challenge to the EPA and its administrator, Lee Zeldin. What are the legal challenges that we’re seeing so far, and what is the basis of their legal standing?

Coglianese: Well, we should note that we’re recording this on February 26, and there’s still time for additional challenges under the Clean Air Act to be filed. There’s a statutory window in which these challenges can be filed. The challenges, when they’re filed, also don’t require much, other than usually a one or two-page statement that we’re challenging this rule. And the legal arguments will develop further. So as to how the these groups and others will argue standing — that is, whether they can even get before a court to hear their objections to what the EPA has done — that, they really haven’t spelled out yet.

And then, even if they can overcome that hurdle of standing, what their arguments will be on the merits they haven’t spelled out either. However, I think we can make some reasonable speculations about both of these issues that they will have to confront. On legal standing grounds, the well established doctrine is that organizations or individuals who are members of organizations need to have some injury. Then secondly, that injury needs to be caused by the challenged government action. And third, that some kind of judicial remedy, such as declaring in this case that the rescission of the endangerment finding was unlawful, would redress their harm.

I think you’re going to see, probably, environmental groups, to the extent that they’re going to put forward — let me stop and say that you only need one party, really, to have standing to go forward. So it may be that groups like the American Lung Association or Clean Air Council or NRDC don’t really build much of a case on standing, because other litigants may enter, and they’re going to sort of rest their standing on those litigants.

Who might those other litigants be? I think two are particularly of note. One is states. And we do know that the state of California and other states are likely to enter challenges. And two, following up on your conversation with Shelley, there’s a whole host of clean energy business groups — the electric vehicle manufacturers themselves — that might well enter the picture. We don’t know what Tesla might do, for example, or CALSTART. I don’t think that’s been determined yet. They have not been happy with this rescission, but whether they will challenge it remains to be seen.

Each of those groups and these environmental groups would have different claims about whether or how they’re injured, whether it’s through members that are suffering from air pollution to states that are suffering the loss of shorelines from a rising sea level, to business groups who’ve had reliance interest or are losing market share or something like that. The causal connection probably is relatively straightforward to make.

The real issue might come down on standing as to whether any of this is redressable. And the EPA has already signaled that it asserts that, “You know what? Given all the greenhouse gas emissions that the rest of the world is emitting, whatever we would have done if we kept the endangerment finding on the books would not really have made a whole hill of beans to these folks, and it’s not really redressable.”

So these are the things on standing that are likely to be there. It’s notable that in Massachusetts versus EPA, Chief Justice Robert’s own signed dissent really focused on standing. So standing is going to be important. You’re wise to ask about it in terms of the arguments. Well, they’re going to really be the sorts of arguments on the merits, that — if we get there — that we’ve been talking about, whether the Clean Air Act encompasses air pollution. It’s going to be about whether Massachusetts versus EPA remains a good precedent, whether the statute contemplated and was designed to address greenhouse gas emissions, or whether it was, as the EPA has asserted, just intended to deal with local or regional air pollutants. And there’s going to be long, long arguments and long briefs on those merits questions, if we get to it.

Stone: So Shelley, I want to take this a little bit step further. This is kind of getting to the odds here, right? So what are the strongest legal arguments that you’re seeing to this point on either side, in support of or against the rescission? And how strong are they in light of recent Supreme Court precedents we’ve seen, for example?

Welton: I thought maybe I would dive a little bit more into the weeds of what the EPA is arguing here. And they’re taking what I think is a pretty strange route. They haven’t come out and brazenly said, “Court, what we’re asking you to do is overrule Massachusetts versus EPA.” They’ve said, “Massachusetts versus EPA was deciding whether or not greenhouse gasses were pollutants for purposes of the act. And they said yes. And what we’re saying,” says the EPA now, “is that that was a general act-wide definition. But when you look at Section 202, specifically about motor vehicles, we think there’s reasons that you should decide that they don’t count as air pollutants for this section of the act. And you should go section by section in the act and figure out, are they air pollutants, given the structure of this section?”

I think this is a pretty strange argument. Because Mass v EPA was itself about section 202, and they said they’re air pollutants. So you have to decide whether or not they endanger. So I think the EPA is really trying to split hairs to distinguish Mass v EPA. I don’t think this is a particularly strong argument, which is why I think Cary is right to frame the real question of the case as whether or not they’re willing to actually overrule Mass v EPA, because I think the distinction is just too delicate and tenuous a one for the court to hang its hat on. Though, I will say, you know, I would never bet against an EPA win on a deregulatory action with this court. So it’s a little bit hard to say.

Coglianese: And I would agree with Shelley that this is a contorted, strange argument to make, and one that was really resoundingly rejected by Massachusetts v EPA. So that’s why, yes, I think if they’re going to prevail, the Supreme Court will have to overrule Massachusetts versus EPA. Maybe, though, with the same kind of logic that Shelley ended with, of sort of the basic deregulatory sympathies, maybe this court will contort itself and say that it’s upholding the rescission, even while retaining Massachusetts versus EPA.

And let’s be real. I mean, I just wrote an article called “Loper Brights’ Disingenuity.” Because when the court overruled Chevron, it didn’t really overrule Chevron. This is a court that has the power, and it may well come up with some contorted reason to rule in favor of the Trump Administration while still looking like it’s observing the precedent in Massachusetts versus EPA. But I don’t see any principled way it really can do that.

Welton: But, you know, the other ground that they’ve put forth as an alternative basis if the court doesn’t want to overrule Mass v. EPA, is that actually they did the endangerment finding wrong. What they were supposed to do was look specifically at motor vehicles and decide, “Do the emissions from motor vehicles endanger public health and welfare?” Instead of sort of like a general endangerment finding about greenhouse gasses.

And what EPA is saying is, if you do that, actually, in the context of global emissions, it’s a pretty de minimis amount of emissions and harm that come from US vehicles. And you know, they’re measuring welfare impacts in terms of sea level rise and global surface temperature increase. I don’t really think that’s defensible. But in any event, they’re saying it would be futile to regulate these emissions. It’s a bold argument, right? Because if you look at US greenhouse gas emissions, transportation is the largest emitting sector. And so if you can’t regulate transportation, as around 28% of US emissions, it’s really hard to imagine how you could regulate anything under their logic.

And I’ll just note, there’s a certain irony to this claim, right? Like, on the one hand, they’re saying it’s a major question whether or not EPA should be delegated this authority, because this is so politically and economically significant. But also it would be futile to regulate these emissions, because it’s such a tiny piece of the overall pie, right? So I don’t know exactly what the court is going to do with that, but you could see them skipping the Mass v. EPA argument and going to this second argument that, you know, essentially, there’s no strong justification for regulating vehicle emissions because they’re such a small piece of the overall global pie.

Stone: Well, that seems to me to be the most contorted — and Cary used the word a couple of minutes ago — contorted reasoning of all. Because under that reasoning, if everybody says, “Well, my slice of the pie isn’t significant within the global climate impact or system,” then nobody has any basis for regulating anything, because it doesn’t become a global collective problem. It just becomes a bunch of people saying, “Well, my slice doesn’t matter, so I’m not going to do anything about it.”

Coglianese: And this is another argument, by the way, that was put forward by the Bush Administration. And again, why I think Massachusetts versus EPA is really central to this. It didn’t convince the court there. But none of those five members of the majority in Massachusetts versus EPA are on the court today. So Shelley may be right that that is another way that this Court may be well convinced to uphold what the Trump administration is doing.

Stone: We’ve talked about this rescission being based on a legal case that’s being brought forth, or a legal framing that’s being brought forth by the EPA. But I want to ask you, how much does a scientific record matter? How much can the court completely ignore the science here, in considering everything that’s going on again, the EPA in 2009 made a decision that these these emissions are harmful to human health. Can the court simply ignore that?

Coglianese: Yes, is the short answer. If the agency is determined by the court to lack legal authority to regulate greenhouse gasses, then all the harms from greenhouse gasses are irrelevant. I mean, you could just analogize and think about, you know, all the harms from artificial intelligence, or all the harms from banking fraud, or all the harms from vehicle accidents. Whatever those might be, the EPA lacks statutory authority to deal with those problems. And it doesn’t matter how many National Academy of Sciences reports there are about vehicle accidents, the EPA doesn’t have any statutory authority to deal with that. So if the court buys the Trump administration’s claim that the EPA just simply lacks authority under the Clean Air Act to deal with greenhouse gasses, then none of the other stuff matters.

Stone: Okay. So Shelley — and I think we’ve touched on this briefly earlier in this same conversation — but I want to go a little bit deeper on this one. You know, some would suggest that the rescission of the endangerment finding is actually just first step in a broader strategy to permanently narrow federal climate authority. What’s your view on that?

Welton: I think that’s right. I think, you know, the extent to which that happens if EPA wins on this is really a matter of how EPA wins. So, you know, if the holding is, Mass v. EPA was wrong, and there really is no authority under the Clean Air Act to regulate greenhouse gasses, you’ve essentially taken away the big legislative stick that exists to deal with climate change in the United States. And although we’ve seen some legislation passed recently that is more on the clean energy incentive side, I think there’s very little chance that you would see new legislation get through on the regulatory side of climate change, given anything like the current composition of Congress. And so, I think there’s ways that this case could get decided that completely hamstring the ability to regulate greenhouse gas emissions.

I think there’s probably other ways that this case could get decided, like in a more narrow understanding of 202 and greenhouse gas emissions from vehicles, that might leave the door open to EPA regulating under other sections. So, like, you could try a new power plant rule, if the ruling on the endangerment finding is very, very narrowly, section 202 vehicle emissions focused.

So I think it’s a little bit hard to predict. But I think it certainly is the intent of the administration, and they’ve said as much pretty clearly, that the goal here is to just eviscerate federal climate change regulatory authority.

Coglianese: Not to disagree with any of that, but also just to highlight how, again, this is authority under the Clean Air Act that we’re dealing with. And so when it comes to motor vehicle emissions of greenhouse gas emissions, to the extent that those are just a function of the burning of fossil fuels, there will be nothing about this case that in any way touches the Department of Transportation’s authority to set fuel economy standards. So a future administration that wanted to tighten those could essentially be doing what the EPA has been doing with its greenhouse gas emissions regulations.

Similarly, with respect to other parts of the Clean Air Act, the EPA, in a future administration, might be able to address certain greenhouse gas emissions because of what they do by way of contributing to or are related to other air pollutants. So methane may still be able to be addressed, but less as — and not as a greenhouse gas emission, but as a contributor to more conventional air pollution. Or some of those more conventional air pollutants, like particulates. If you tighten those standards that may essentially force greater fuel efficiency or fuel switching, that could have real benefits in terms of reducing greenhouse gas emissions. So the regulation is not completely off the table, but it would have to proceed in a different route. The agency would have to be very careful not to make it look like it’s just engaging in pretextual backdoor climate change regulation. But nevertheless, these these options would exist.

And lastly, with respect to Congress, I agree with Shelley that passage of legislation that might overturn a Supreme Court decision here would be very hard to see being adopted. It isn’t as hard to see a future Congress using the reconciliation process to put in place further tax incentives and subsidies for a shift to cleaner fuels. And those, in reality, could well be as effective, if not more effective, than the exercise of regulatory authority under the Clean Air Act.

Stone: And I just want to go back a second and explicitly connect some dots here. You mentioned, a minute or two ago, regulations on methane emissions. And those regulations are also based in the endangerment finding, right? So that just kind of shows you the range of regulations of greenhouse gasses in various industries that go back to this 2009 EPA finding.

Coglianese: As Shelley said at the outset, some of these more specific provisions do also call for their own separate endangerment findings. But once this one falls, and if the Supreme Court affirms it, the structure, and the text and the so forth is so similar that these others would also fall too. Of course, I don’t think this administration is likely to wait for a resolution by the Supreme Court to roll some of these other ones back. But essentially, you’re right, yes. That this would be the key touchstone for all sorts of what have been climate change regulations by the EPA. But you could get some of those greenhouse gas emissions reductions as sort of side benefits to regulating more conventional pollutants and provisions in the Clean Air Act that deal with those more conventional pollutants.

So Cary, I want to ask you here, procedurally, what comes next in the legal battles over the endangerment finding? And how likely is the Supreme Court to eventually review a case on this, and what will determine whether the court actually takes a case?

Coglianese: So, there is this limited window in which these petitions can be filed after the EPA has issued its rescission. We still have some time left on that clock. So we’ll wait and see who joins and challenges this rescission. At the same time, you’re also going to have, then, other groups that want to intervene on behalf of the EPA and defend this. So look for some business groups to try to do that.

Then it’s going to be heard before the DC Circuit, initially before a three-judge panel. If the DC Circuit grants a petition for what’s called on bank review, then it could be reviewed by all the judges on the DC Circuit, or it might go then directly to the Supreme Court. We’ll have to see. But it’s destined to go to the Supreme Court. I don’t think there’s any doubt about that. But it’s likely to take a couple of years at least. It wouldn’t be surprising or out of the ordinary for that to happen.

That’s one of the reasons, by the way, going back to why the EPA has taken this strategy of trying to move to argue that it lacks statutory authority. That’s a much quicker route. You don’t have to build the factual record that rebuts all the climate science. You can just dust off the old briefs, essentially from before Massachusetts versus EPA, and move forward now. It’s a much quicker strategy, and maybe the EPA is hoping, I’m sure, that they can get this before the Supreme Court before the end of the Trump Administration.

Stone: Okay, so Cary, a follow-on question here. So if the EPA is found to not have the authority to regulate greenhouse gasses, what does that mean for state level climate regulation? Does the federal retreat free up the states or does it constrain them?

Coglianese: Well, this is going to be another point of litigation that’s going to play out for some time, probably well past the Trump Administration. Normally, if there’s no federal legislation, then states are free to exercise their what are called “police powers” or their “general welfare powers,” and protect their public from harms, and issue various pollution standards. The Supreme Court has already held that some of these actions based upon state law, nuisance suits and tort litigation can’t go forward because there is federal regulation in this regard. And it’s been preempted. These state claims and state policies that might be adopted are preempted by the federal legislation, by the Clean Air Act.

Now, what happens if the Clean Air Act no longer is regulating greenhouse gasses? Then that would seem to no longer support any kind of federal preemption. And the EPA doesn’t like that. This administration doesn’t like that. And they’re arguing no, it would still be preempted. When it comes to vehicle emissions, they’re going to say that, you know, Title Two is a very comprehensive structure in the Clean Air Act to deal with mobile source air pollution, and if it doesn’t cover greenhouse gasses, then it means that states shouldn’t start getting into the mix. Or that — more likely, what they would say is that regulating greenhouse gas emissions from vehicles is tantamount to regulating fuel economy. And fuel economy, remember, is the Department of Transportation. And that statutory authority will still remain, and that statutory authority preempts automobile regulation.

But there’s a host of state laws that could be adopted litigation under existing state common law. And you know, we even have a few states, like Montana, that have been found to have state constitutional protections that deal with climate change. This will be where it will go. And I think, you know, picking up on a point that Shelley was mentioning with respect to the industry posture, all of this is going to introduce a tremendous amount of uncertainty into the regulatory climate. No pun intended.

Stone: So I think we have time just for one more question here. And I want to direct this one to you, Shelley. And it kind of comes out of what Cary was just talking about in relation to the states. And I want to ask you, what effect would this repeal have on the lawsuits that have been brought by states and cities alleging corporate liability for climate change? How will those be impacted?

Welton: I think this is going to be a really interesting space to watch. Earlier this week, the Supreme Court granted cert in a case called Suncor Energy versus Boulder County, which is basically asking the exact question that the endangerment rescission implicates, which is, are state and local lawsuits seeking to recover damages from private companies for climate harms preempted by federal law? And this case is really just emblematic of dozens of similar cases that are going on from states across the country.

And you know, the big argument that states are making, and cities are making, in these cases, is that oil and gas companies have known about climate change and they have publicly denied its existence or sought to sow doubt about it as they exacerbate the climate crisis. And thereby, they’ve caused millions, billions of dollars of damage to property, to residents, right? And so they sought to bring these sort of very common law grounded damages claims.

And the argument on the other side has been these are preempted by federal law. And a piece of the preemption argument is the Clean Air Act argument. There’s also parts related to foreign affairs, sort of like more general executive power. But if the EPA is now arguing that the Clean Air Act does not afford it the authority to regulate greenhouse gasses, I think it’s much harder for them to round out this preemption argument against these state common law claims. Which is not to say that they will suddenly wildly succeed. I think there are other challenges to bringing them. But this has been one of the primary lines of defense, and I think the Trump administration just made it a lot harder for the oil and gas companies to mount this defense.

Coglianese: The bottom line is, Andy, you’re going to have a lot of additional Energy Now Podcasts that you could be running on these issues.

Stone: I’m sure. [Laughter]  That’s all taken care of.

Welton: That was a whirlwind.

Stone: Both of you, Shelley and Cary, thank you very much for talking.

Coglianese: Thank you, Andy, always good to be with you.

Welton: Thanks so much for having us.