What’s Next for Environmental Law in 2026

You're listening to People Places Planet, the official podcasts of the Environmental Law Institute, a nonpartisan, nonprofit, research, and education institute making law work for people, places, and the planet. If you enjoy the podcasts and want to support our work, consider donating at ELI.org/donate. Welcome listeners to another episode of People Places Planet. I'm your host, Sebastian Duke Arreos, and in today's episode, we're taking a step back and a step forward. We'll be looking ahead to some of the environmental law and policy issues we'll be watching closely in 2026 by first reflecting on the most consequential legal regulatory and institutional developments of 2025. The episode is structured as a guided tour through the year. We'll begin with the US Supreme Court, walking through key decisions from the last term and previewing cases that could shape environmental law in the year ahead. From there, we'll dig into major shifts in administrative law and governance, from changes to NEPA review, to how courts are treating agency expertise, public participation, and deference. We'll also explore a growing theme from 2025. The way climate changes increasingly being framed not just as a policy challenge, but as a matter of legal rights and accountability, both in US courts and on the international stage. And finally, we'll turn to how these big legal debates are playing out on the ground. From data centers and infrastructure to clean water and cooperative federalism, we'll look at what happens when federal authority shifts, state responsibilities expand, and longstanding environmental tools are redefined or removed. Throughout the episode, you'll hear from legal scholars, practitioners, scientists, and policy leaders brought together through ELI convenings over the past year, offering insight not just into what happened in 2025, but why it matters as we head into 2026. To start us off, we will recap some of the important environmental and energy law decisions that came out of the US Supreme Court this year. Each year, ELI brings experts together for our annual Supreme Court review and preview webinar, where we break down what the court decided in the last term and what's coming next. This year's conversation was moderated by Jay Austin, a senior attorney at ELI, and featured three leading voices in environmental law, sharing Jacobs from Berkeley Law School, Pat Peranto from Vermont Law School, and Gerald Torres from Mio Law School. In this segment, you'll be hearing some highlights from that webinar. To get more information, be sure to check out ELI's resources on the 2025 SCOTUS term. The first case we'll talk about is city and county of San Francisco versus EPA, where the Supreme Court delivered a major clean water act ruling that limit what EPA can require in discharge permits. During heavy rains, the city of San Francisco's combined sewer system can overfill and discharge pollutants into the Pacific Ocean. The clean water act requires the city to have a nip-dees permit for these discharges, but the newest permit issued in 2019 by EPA had an end result limit, which meant that the city would be violating the permit if the receiving waters, in this case the Pacific, fell below water quality standards after the discharge occurred. By a five-four vote, the court held that EPA may not include end result limits and nip-dees permits. The court reason that the clean water act is built around regulating what is discharged through effluent limits and narrative requirements. The court believed that EPA should tell permitties what they must do in advance, but not hold them liable for downstream water quality outcomes that can be affected by weather or other polluters. However, the dissent noted that in the past, EPA often issued permits with end result requirements when it lacked the information needed to develop tailored effluent and narrative limitations. Now that it can't do that, it might simply refuse to issue permits in such situations. Here's what Pat had to say about the decision during the webinar. So to start us off in San Francisco versus EPA, it's clear that Justice Alito not surprisingly was concerned about the fairness aspect of conditions like the ones in San Francisco where EPA did not spell out what San Francisco needed to do to deal with combined sewer overflows. And so you have a legitimate concern about what exactly is the permitties supposed to do. In the San Francisco case, it was more complicated than that because EPA had been trying for years to get San Francisco to provide more information about their combined sewer systems and alternatives to reduce the impairment of the receiving waters, including beaches on the Pacific coast. Beyond that, Alito was concerned about the impact on the shield provision of the Clean Water Act, a legitimate issue again. But the point there is, as Justice Barrett pointed out in her descent, that there really is no problem with the shield provision because if you're in compliance with the permit, you are immunized from enforcement. And if you have a permit condition that you claim is unreasonable and you can't figure out how to comply with it, what's the answer to that? Challenge the permit on the grounds that it's arbitrary and capricious that it's unreasonable. So don't take the permit and then later on say, I don't know what the permit requires me to do. That's where we are with the San Francisco decision. The next case we'll talk about is NRC versus Texas. In this case, the Nuclear Regulatory Commission, or NRC, it should a license to a private company to build a nuclear waste storage facility in Texas. A separate group of mineral lease holders were the ones to challenge this license, despite not being parties to it. The U.S. Court of Appeals for the Fifth Circuit vacated the license, holding that neither the Atomic Energy Act nor the Nuclear Waste Policy Act authorize the NRC to license private and term storage facilities. In a 6-3 decision, the Court reversed this ruling, holding the only parties who formally participated in the NRC's licensing proceeding can challenge those decisions in court. Here's some insight from Sharon Jacobs on the decision. I think it's an important case for energy environmental law, but it also raises an interesting jurisdictional question. So the very quick background refresher is that during the licensing proceeding, there was a group of mineral lease holders from the area, and they wanted to intervene in the licensing proceeding. But the Nuclear Regulatory Commission didn't allow them to do so. However, the mineral lease holders did comment on the environmental impact statement. The license was granted, and this was several years ago now, but it was challenged. So this lawsuit is about the challenge from the mineral lease holders called Baskin and Taxis, and so there were two questions before the Supreme Court. The burst was a threshold question, and it's actually the question on which the court resolved the case, which is, could the plaintiffs bring this lawsuit at all? They brought it under a statute called the Hobbes Administrative Orders Review Act, and to bring a challenge under that statute, you have to be a party aggrieved. So the question is, were they actually parties since they were not interveners in the licensing before the NRC? And then the second question, if they could bring this case is the statutory one, whether the Nuclear Regulatory Commission has authority to issue licenses like this to private entities for offsite storage of nuclear fuel. So the Supreme Court held that neither Texas nor Faskin could seek judicial review of this decision because they were not parties to the commission's licensing proceeding. The court didn't actually get to the merits question about the NRC's authority, but you'd never know it given how much time both the majority written by Justice Kavanaugh and the dissent written by Justice Gorsuch spent talking about the merits question. It seems pretty clear that a majority of the court thinks that there is authority for the NRC to site facilities like this. This is good for the NRC, but I would argue it's good for the nuclear industry in general because this problem of where to put nuclear waste is a significant stumbling block when it comes to build out of nuclear power. In June, the Supreme Court also decided on diamond alternative energy LLC versus EPA, a case where fuel producers challenged EPA waivers granting California's authority to regulate full economy outside of the Clean Air Act. Under the Clean Air Act, states are generally prevented from setting stricter vehicle emission standards than federal law. However, Clean Air Act Section 209B provides California with a waiver, allowing it to set its own standards. The fuel producers argued that stricter standards would harm their business monetarily. This case was mainly related to standing, and in a 7-2 decision, the court ruled that the fuel producers did have standing to challenge EPA because invalidating the waivers would redress their monetary injuries from decreased fuel sales. Here's what Pat had to say about the decision. So we've got a diamond alternative energy versus EPA a 7-2 decision. The amazing thing about this decision is pointed out by Justice Jackson and her dissent is that an environmental organization would never have had standing to do what the biofuels producers were able to do here. Their argument is that there's going to be more electric vehicles on the road and less vehicles that need our biofuels product. There's a lot of intervening actions that have to take place before that would happen. It's rather attenuated. But if the biofuels producers that are downstream of the actual decision that EPA reached have standing, then maybe environmental groups will be happy to see a decision like this and renew some of the arguments they've made for standing in similar circumstances where they're not directly affected. So now that we've gone over a few of the major cases that were decided this year, ELI's 2025 Annual Scotus Review and Preview also dove into what the panelists were expecting to see during the 2025-2026 term. First, Pat Pantole discuss Chevron versus Plaquemines Parish in Louisiana, a case that is scheduled to be argued on January 12th. This is Chevron versus Plaquemines Parish and the legal question is whether a contractor can remove a state filed lawsuit to federal court when being sued for oil production activities undertaken to fulfill contracts with the federal government and just for background, all of the circuit courts have concluded that state initiate liability cases against oil companies don't belong in federal court. They've all been remanded to state court. There are almost 40 of them. The difference with the Plackamons case is that in the climate cases, the theories of the liability all had an element of deception, false advertising, failure to warm. That's not involved in the Plackamons case. It's going on with Louisiana, because they're losing their coastal wetlands completely. It's a combination of sea level rise, subsidence, but also oil and gas production. So the gravamen of the cases against the oil companies are you didn't comply with our Louisiana coastal protection mechanisms, including restoring wetlands that your construction activities have destroyed. Chevron has reason to want to have moved these cases to federal court because they just lost the first case. And in a nutshell, this is a case about where these losses are going to be tried. It's not determination. And finally, to close out our preview, we'll turn to the Supreme Court in 2026. Sharon Jacobs will walk us through several cases expected to be decided this term that goes straight to the scope of presidential power and the limits of executive authority. The very quick version of this case is that there have been challenges to the president's authority under a statute called the International Emergency Economic Powers Act to issue broad tariffs. And both the DC District Court and the Federal Circuit have found that the statute does not grant the president powers to unilaterally imposed tariffs. And one of the interesting things about both of these decisions is that they invoke the major questions doctrine, which is this idea from West Virginia versus EPA that we require a clear statement from Congress when an agency proffers an interpretation that would represent either an expansion of its powers or presents a question of debat economic and political significance. And this kind of authority, the Trump administration's claiming for the president to issue these broad tariffs is a real departure from how that statute's been implemented in the past, it is that kind of major question and it's an opportunity for the court to tell us a little bit more about that doctrine. And that tariffs cases just one piece of a much bigger picture this term, Sharon also flagged the way of emergency docket cases that raise broader questions about presidential control over agencies personnel and federal spending. A lot of the cases this year on this emergency docket have involved challenges to the president's authority to remake restructure administration lower courts in many cases have stayed those actions and the Supreme Court has jumped in on an emergency basis to allow those actions to go forward. One of the things that we have seen is a Trump administration specifically removing the heads of what we've classically thought of as independent multi member agencies, the Trump versus slaughter case is actually going to come before the court in December involving the removal of an FTC commissioner. This, of course, has obvious impacts for energy law, especially, but for environmental regulation as well. EPS had can already be removed by the president for no reason, but for the nuclear regulatory commission, they have these kind of shielded boards. The other last buck that I wanted to talk about here have to do with agency officials and with funding decisions there have been a number of efforts to remove agency officials from their positions, though many of these efforts have been challenged and in many cases district courts have required reinstatement of employees. A number of cases have been brought to the Supreme Court on this emergency docket in which the Supreme Court again barred those lower court judgments were going into effect. So McMahon versus New York Trump versus American Federation of government employees OPM versus American Federation of government employees and funding decisions, the administration has withheld grant funding and there have been challenges to those efforts as inconsistent with the laws violating the impoundments control act DOE versus California. Trump versus Global Health Council NIH versus American Public Health Association. There are a few more examples, but I think you get the idea is that we live in a really unusual era for Supreme Court decision making in which courts are being asked to essentially work year round overseeing the decisions of lower courts on vital questions of government authority and separation of powers. Another major issue that ELI has been tracking closely is the recent wave of changes to the National Environmental Policy Act better known as NEPA. These shifts followed the Supreme Court's decision in seven county infrastructure coalition versus Eagle County Colorado. A case we intentionally held back on earlier so we could dig into it in more detail now back in July ELI hosted a webinar titled the future of NEPA review unpacking the seven county infrastructure coalition decision. The conversation was moderated by ELI staff attorney Jared Paige and featured a panel of experts, Kiriti. Love from Earth Justice Jim McElfish from ELI Justin Pito from the University of Arizona College of Law and Fred Wagner from Jacobs. Over the next few minutes, you'll hear highlights from that discussion. We'll start with a brief overview that Jared gave during the webinar of this case and its implications for the future of NEPA. As a brief backstory, in connection with the approval of an 88 mile rail line in Utah, the surface transportation board conducted an environmental impact statement or EIS. The board's EIS indicated that oil production was a foreseeable result of the rail line and they did include greenhouse gas emissions estimates that might result from the crude oil that was carried on the line. EIS did not do a detailed analysis of these emissions or other environmental impacts from increase in oil production and refining. After the board approved the decision, Eagle County and other environmental organizations filed the challenge alleging among other things that the board did not take the requisite hard look in the EIS looking at the upstream in terms of more oil production and the downstream in terms of more refining and combustion. In 2023, the DC Circuit issued an opinion finding that the EIS was inadequate and that the board should have done more to look at those upstream and downstream impacts. A coalition of Utah counties sought review in the Supreme Court who issued their decision on May 29. The court by an 8-0 vote reversed and demanded the case back to the DC Circuit. The majority held that the DC Circuit failed to afford the board the substantial deference that NEPA requires and that the court incorrectly interpreted NEPA to require the board to consider environmental facts of upstream and downstream projects that were separate in time and place from the rail line. So the decision really narrows the scope of NEPA review and will likely have lasting impacts on federal infrastructure project proposals. As Jerry mentioned, a key concept in this case was deference. Essentially, how much could court trust agency's judgment when deciding what to include and how much detail to provide in their environmental impact statements? Here's how each of our panelists understood deference in this case. I think the important takeaways from you deal with what the court means by deference. Deference has always been part of the landscape of NEPA litigation. What's interesting is that we still have a long history of Supreme Court presidents cited by this court, all of which call for agencies to take a hard look at the environmental effects of a proposed agency to action. So what does it mean to be deferential to an agency's implementation while also ensuring the hard look is still occurring? And the majority opinion suggests a least three dimensions to the deference. One is what details are included and what is the level of detail. The second area is what significant environmental effects are included and the analysis and what feasible alternatives are included or excluded. The third, the court will defer to agencies decision to include or not include indirect effects and how far to go up or down the chain or with respect to cumulative effects. So it's interesting that we have some guidance as to what the deference is applied to, but we don't have much guidance as to how that interacts with hard look. NEPA has always been a common law statute. In other words, how do you know that you're doing enough as an agency? You know when the court say you're okay. What the Supreme Court stressed is so long as the agencies and project proponents are doing a reasonable piece of work to assess impacts and make an educated decision, that's what deference really means. Why did they have to say that after all those years, Justice Cavanaugh called it a course correction because of the bulk and the intensity and the scope of NEPA analyses over the course of years. So the court begins by saying that the central principle of judicial review in NEPA cases is deference and it ends by criticizing the way that, quote, some courts have reviewed agency's NEPA analyses. But what's odd about the opinion is it doesn't identify any part of the DC circuits decision that was insufficiently deferential and that I think would have provided that kind of clarity that the court says is important because agencies would know what they don't have to do and courts would know what they shouldn't do in the future. Another important element of this case was the scope of review. what should and shouldn't be included in an EIS. Here's what the panelists took away from the court's decision. - The SCOBA review has always been focused on the project in context. Where are the indirect effects of the project? Where are the cumulative effects of the project when viewed in the context of other things that are going on in the environment? And having the court decision restressed the emphasis on attestions to the project in its appropriate context. - The opinion says a few times that NEPA's focused on the proposed action. But it doesn't discuss the text that proceeds those words, which refers to the reasonably foreseeable environmental effects of the agency's action. And so someone reading the opinion is left to figure out how the text of NEPA works as a whole when you consider all the words in the text. And then last, I'll say that the court is pretty clear that it thinks that separate projects are outside of NEPA's scope. But then it sort of injects a lack of clarity into that discussion because the court says, well, of course, there's going to be a gray area. And then it doesn't give any guidance on how to wade through that gray area when it comes to looking at the statutory text. - I think an interesting wrinkle though is that in some ways the analysis is aided by the fact that the case of dealing with NEPA process that was not under the fiscal responsibility, because the FRA added the language reasonable foreseeability to the statute for the first time. - So I'll be curious to see how when we begin to see the decisions under the FRA with the reasonable foreseeability language in the statute, how works then reconcile through this difference in seven counties and low-prepared document. - Lastly, the panelists were asked whether they thought this decision would affect the nature of permitting in the future and what impacts they think this case might have. Here's what they said. - I think the recent developments that the sweeping away of the secure regulations and the changes in agency regulations and procedures have raised is how much public participation will there be? If, in fact, agencies decide that there will be no public participation and no preparation of a draft environmental impact statement, it is required to defer and to what extent does the court defer on that particular issue? - Where this opinion is gonna bite or not is in the following sentence, yes. We had, and here, thousands of pages of analysis, extensive public comment. The court looked at it and said, "It feels like it was nuts." What happened when you had a 28-day EIS with no public comment? That is eight pages long and provides almost no information. Do we apply the opinion intuition? Or the court's gonna say, well, if having counties told us to be paper-duff wrenching, when those issues bubble up in the courts, that is going to determine how neat that, as it's currently constituted, applies and report. - And these questions with respect to NEPA lead directly into what changed at CEQ and across the federal agencies this year. Over the past year, agencies have rolled out sweeping updates to how they implement NEPA, following the Council on Environmental Quality's decision to rescind its government-wide NEPA regulations. To break down what changed and why it matters, here's Jared Page. Well, 2025 has been quite a year for NEPA. If we were talking about NEPA in a 2024 wrap-up, it would sound very different. In late 2024, in a routine NEPA case, sort of out of nowhere and a surprise to pretty much everyone watching, a divided DC circuit panel concluded that the Council on Environmental Quality, the agency that's been responsible for figuring out how NEPA works in practice for agencies across the government for decades, did not have the authority to issue NEPA regulations. Ultimately, the full court of the DC circuit said that decision was Dicta, but it was big news at the time and definitely would have made our end of 2024 list. Either way, that's old news. And the decision has been supplanted by much more consequential developments that have taken place in 2025. In January, everything kicked off with a day one executive order that revoked an executive order issued by President Carter. That was a big deal because the Carter order provided the basis for CEQ's authority to issue regulations governing the NEPA process. Those regulations had, since the late 1970s, established a common blueprint for all agencies to use and really ushered in a relatively stable and predictable era of NEPA implementation for decades. In fact, since the late 1970s, dozens of federal agencies had supplemented the CEQ regulations tailoring them to their own use. Congress had legislated against CEQ's well understood authority, including as recently as 2023 in the Fiscal Responsibility Act. And the Supreme Court had acknowledged the deference that CEQ's NEPA regulations should get. That all changed in January with the executive order that directed CEQ to propose rescinding the NEPA regulations and issue new guidance to agencies on how to implement NEPA. CEQ did one better and in February issued an interim final rule that didn't just propose it rescind the regulations, it rescinded them. CEQ also offered up guidance and gave agencies 12 months to develop their own set of NEPA procedures. And so in one move without any public input, nearly 50 years of CEQ's NEPA implementing regulations that offered a consistent and predictable process for agencies and all other stakeholders was wiped away. Since then, in the absence of any overarching regulations, agencies have begun to go it alone, each carving out their own NEPA path. And while CEQ has provided guidance that agencies can use, early announcements have revealed that processes can vary sometimes on major points on the issue of public input, for example, it's a mixed bag. Some agencies like the Department of Defense have indicated they plan to continue to offer draft environmental impact statements for public comment, but others like the Department of Interior do not appear poised to do the same and will all be waiting to see how agencies proceed in 2026. Thank you, Jared. Now, as we look toward 2026, one of the most consequential developments from 2025 is how courts are increasingly treating climate changes of rights issue, not just the policy debate. A key example came out of Montana this year where a youth-led case reshaped how climate harm is understood in constitutional terms, at least at the state level. We discussed this case in a previous podcast with Jared and Helene Krasnoff, Senior Attorney and Director of the Climate Judiciary Project at ELI. As Jared explained then, when the case reached the Montana Supreme Court, the state's appeal focused almost entirely on the legal questions, things like standing and whether the youth plaintiffs could bring this kind of claim at all, rather than disputing the underlying science. And that distinction matters, because while the science went largely and contested in this case, the court's decision ultimately focused on Montana's constitutional protections. Here's Helene on what the court decided and why it was such a significant ruling. The Supreme Court ruled in favor of the youth plaintiffs. They won. The court in its ruling did make clear that, quote, plaintiffs showed a trial without dispute that climate change is harming Montana's environmental life support system now and with increasing severity for the foreseeable future. End quote. But most of the opinion was about the law. Montana has one of the strongest constitutional protections for environmental rights in the whole country. The court ruled that that rate includes a right to a stable climate system. So that ruling is powerful, but also carefully grounded. The court wasn't recognizing an abstract climate right. It was enforcing a specific constitutional guarantee against a specific legal barrier. The provision that was challenged specifically bored the state from considering greenhouse gas emissions when it was doing environmental reviews. And the court read that that provision violated the Montana Constitution. The plaintiffs weren't just making general claims about climate. They were saying this specific Montana law is violating their right that they are guaranteed by the Montana Constitution and the state Supreme Court agreed. And so this case was able to move forward. Well, as we look ahead, that specificity matters. It shows a path forward for climate and human rights claims, one grounded in concrete laws, concrete harms, and enforceable rights. But the real test comes after the win. Future cases are likely to test the boundaries of this constitutional right. The analysis is starting to consider climate change impacts, but maybe not all of the indirect and cumulative impacts associated with a particular project. And that tension between landmark rulings and cautious implementation is something we're likely to see more of in 2026. As we head into the new year, the significance of these cases may lie as much in their factual foundations as in their legal holdings. Climate change is increasingly treated as a lived harm with legal consequences. And courts are beginning to grapple seriously with what that means for rights, governance, and the accountability. And that shift isn't limited to US courts. In 2025, we also saw this rights-based framing of climate harm take center stage in the international courts. For the first time, the world's highest court weighed in on what states, oh, legally, when it comes to climate change, human rights, and intergenerational harm. To help unpack what the court decided and why it matters beyond the Hague, here's Margaret Balagic-Gon-Von-Rotts, a public interest environmental law fellow here at ELI, who's been following how this advisory opinion Could shape court cases around the world? In July, the International Court of Justice delivered its advisory opinion on the obligations of states with respect to climate change. The ICJ's unanimous and groundbreaking opinion made headlines throughout the latter half of the year because the court stated that states do, in fact, have an obligation to address climate change. This obligation comes from more than just existing climate agreements like the Paris agreement. States are also bound by customary international and human rights laws to tangibly address climate change. Court made it clear states must achieve the highest possible ambition in their naturally determined contributions to achieve the 1.5 degrees Celsius goal, and they must use the best available science to do so. The court also highlighted that the right to a healthy environment is indeed a human right, and that right includes the right to a healthy climate. These obligations mean that states may face legal consequences, including reparations to injured states for "wrongful acts" and "such as failing to regulate fossil fuel consumption or the granting of fossil fuel subsidies." How will this impact climate litigation moving forward? The opinion will be a vital tool for regional and domestic courts to clarify state obligations. But the court also spoke directly to private actors and the need for states to regulate them, as part of their duty to exercise due diligence. In the last few months, several cases have already engaged with or cited the opinion directly. For example, a federal court in Canada acknowledged the persuasive, though not binding, authority of the ICJ, and how the opinion may inform constitutional interpretation. And in Brazil, a federal court cited the opinion statement that mitigation measures must cover fossil fuel emissions, and the judgment called the Brazilian government's exclusion of coal from licensing conditions "inconsistent with the enhanced duty of care" and "outlined by the ICJ." For 2026, a few questions remain. How will the ICJ opinion play out at future cops, given its lukewarm reception in Brazil at COP30? Will the opinion continue to be a basis for future climate litigation? How will the opinion affect the petition currently at the African Court of Human Rights, requesting an advisory opinion on climate change in human rights in Africa? Will that court mirror its inter-American counterpart, which issued its own advisory opinion on the climate emergency, just days before the ICJs? And will these advisory opinions have any sway in American climate cases, or even be used in complaints against climate majors or governments, given that international and regional courts have non-binding authority in the United States? These questions suggest a significant shift in the international climate space, toward stronger ambitions and more concrete climate obligations. The ICJs decision is just one part of a broader shift we're seeing internationally. Taken together, these developments point toward a growing recognition of environmental harm and responsibility. But, as we turn back to the United States, that momentum contrasts sharply with a domestic effort that could dismantle the core legal foundation of federal climate regulation, the endangerment finding. Adopted by EPA in 2009, the endangerment finding is a legal foundation for regulating greenhouse gases under the Clean Air Act. In short, the finding concluded that GHG emissions endanger public health and welfare. Heading into 2026, a final decision is still pending and expected after the US EPA proposed in August 2025 to rescind its original 2009 finding that greenhouse gas emissions endanger public health, aiming to remove the legal basis for most federal climate regulations, including vehicle emission standards. The focus is not on disputing climate science, but on reinterpreting EPA statutory authority. In other words, whether the Clean Air Act requires EPA to regulate greenhouse gases in the way that it has over the past decade. What makes this moment significant is a scope. Rather than targeting individual climate rules, this approach goes to the foundation itself. In September, ELI brought together experts to learn about the extensive scientific research that informed the endangerment finding and how our more advanced understanding of climate science substantiates its legitimacy, the conversation was moderated by John Doherty. Science and policy analysts at ELI and featured Christina Dahl from Climate Central, Christy Ebby from the University of Washington, David Lobel from Stanford University, and Jason Seminoe, former climate change specialist at the US EPA. The endangerment finding was grounded largely in national and international scientific assessments. So what does that say about the strength of the science itself? Here's what our panelists had to say. The endangerment finding was informed by extensive research, drawing primarily from authoritative scientific assessments from the intergovernmental panel on climate change, IPCC, the US Global Change Research Program, and the national academies. And again, the affirmative determination was made in 2009 based on where the science was in 2009. Fast forward 16 years in 2025, the evidence that Link's greenhouse gases to harms has only gotten stronger. Countries have to agree basically at every stage in the IPCC for a long time. So when we go through the approval phase and basically sentenced by sentence, any country can object to whether we really have the evidence. And so as a scientist, you go into this knowing that anything you put into this report, you have to be very careful about the source of that information. You would never rely on a single study. You have to rely on multiple lines of evidence. You have to be very careful about your language, and so it's quite a high bar. And this process speaks to how rigorous the science behind the endangerment finding is. But at the center of EPA's rationale for appealing the endangerment finding is a report drafted by the 2025 Climate Waking Group, a group of five independent scientists assembled by current energy secretary Chris Wright, which claimed that climate models contain exaggerated predictions of future warming. Here's some insights from our webinar regarding the report. There were many things that were simply omitted. For example, in a section about how hurricanes are changing, they address the fact that hurricane frequency is not increasing, which is fairly well known in the science community, and neglected to report the fact that hurricanes are increasing in intensity. Some way that I tend to think about this DOE report is simply by the number of authors and contributors for the last national climate assessment. There were 750 authors and contributors for the last IPCC report. The number I found was 721 in this climate working group had five, right? So we come back to this idea of representation of the consensus as the strongest way to represent the science, and this very clearly does not represent consensus or a transparent process. So while the endangerment finding debate focuses on whether federal climate authority can be rolled back, another set of questions is emerging around how federal and state authority actually operates on the ground. One of the clearest places we're seeing that tension play out is around data centers, which have become a major testing ground for our federalist framework. Driven by explosive demand, data center growth has been a dominant issue throughout 2025. And toward the end of the year, the federal government took a notable step in this space with broader implications for infrastructure governance. In December, the president signed an executive order titled "Insuring a National Policy Framework for Artificial Intelligence." While that order stopped short of directly preempting state laws governing data centers, it reflects the administration's concern about a fragmented regulatory landscape and signal strong federal support for continued industry growth. The order seeks to limit what the administration views as overly restrictive approaches to AI and compute policy, including by directing the Attorney General to challenge certain state laws and by encouraging federal agencies to consider the use of funding lovers. At the same time, this executive order sits alongside other federal actions that could significantly expand federal influence over data centers. Together, these moves have raised questions about how much room states and local communities will have to manage the real world impacts of data center development. To unpack a little bit of what this means for data centers, moving forward, here's some initial reactions to the executive order and what to watch next from Alexandra Nelson, ELI's program director for the digital economy and the environment. I think it's very important for the federal government to pay attention to AI policy and data center needs, because they're reshaping our energy-grade land use decisions and water resource planning. As a result, we've been seeing increased attention on the issue from both the Trump and the Biden administrations. This most recent executive order from the Trump administration actually leaves the data center growth issue to the states. Stating that the new federal policy framework should not seek to preempt state laws pertaining to AI compute and data center infrastructure. But there's no question that this administration is supportive of data center industry growth and is flexing its authority through other channels, such as the Department of Energy's recent directive to the Federal Energy Regulatory Commission to open a rulemaking about large loads, which are most often data centers, connecting directly into the transmission grid as end users, expanding its jurisdiction significantly. States are pushing back against the expansion of federal authority in this area because of issues related to the cost of electricity and local community concerns. And I think we're going to continue to see this tension grow next year. 2025 was a year of speculative growth for the data center industry, with ever increasing investment and project announcements. But I think 2026 will be the year where we see which data center projects are actually getting built and how the energy grid and water providers need to change to accommodate them. And this is also where the idea of cooperative federalism really comes into focus. It's something we highlighted this year through our 2025 Environmental Achievement Award, which honored Ben Grumbles and the Environmental Council of the States for their leadership and strengthening state federal partnerships. As their work underscores, environmental law impacted depends not just on federal authority, but on states having the resources, flexibility and trust to both carry out environmental programs on the ground and serve as the laboratories of democracy in emerging issues. Without that partnership and without sustained investment, our federalist system can't deliver as it's intended to. To say a little bit more about the importance of cooperative federalism, here's Jim Kenney. The Cabinet Secretary of the New Mexico Environment Department from our podcast earlier this year, celebrating collaboration, echoes, and the future of state-level environmental policy. The states are so reliant on what Congress intended for these environmental programs to work, which is Congress said the federal government and states are to implement these programs and then states took primacy or delegation of these programs nationally. So when Congress is not funding states, then states are not able to deliver on that proposition of cooperative federalism. What that looks like is communities in New Mexico and all across the country are going to have less funding to provide permits to provide water infrastructure projects to really further the economy in those states. It's a critical time, a critical juncture, and it's exactly why Ecos is lobbying in a bipartisan way to ensure that Congress understands that a lack of funding will actually slow our economies and not build them. I think about New Mexico as being typical of many other states and let's talk about drinking water. Now whenever we turn on our tap, we assume that we're going to get safe and reliable drinking water. That is not often the case across many of our states and the issue there is operators who run those drinking water cheap implants as well as those technicians who serve in that capacity. You can't find them, they're hard to find. Drinking water cheap implants all across the U.S. are having trouble with that issue. So states often step in and provide technical assistance. People may be familiar with us providing grants or maybe providing permits or even taking enforcement actions. What they don't see is on a day-to-day basis, state employees are providing technical assistance to the safe and successful operation of those facilities all across the U.S. And that function that we perform if not funded or not happening is a loss in that shared proposition of clean water. So it's really important again that we continue to think about what are our priorities as states, clean, reliable drinking water. You need that for communities, you need that for economic development. Think about this. What community is going to get a data center, right? If that data center, those employees have to live and drink water that has high levels of arsenic in it or high levels of chlorinated byproducts. So you can't separate out the economy from clean, reliable drinking water. And nor would we want to. We want to continue to provide that technical assistance, but we need to be funded in order to make that happen. So that's just one example of how states are working cooperatively to provide that technical assistance. Across environmental law in 2025, we've seen that states are being asked to take on more responsibility while the federal government abdicates responsibility by narrowing or shifting its role. These changes are bound to affect the balance of cooperative federalism, where states are the primary implementers of many environmental programs, but they still rely on clear federal standards, funding, stable legal authority, and meaningful permitting and enforcement tools to do that work effectively. One place without dynamic is playing out very clearly is in waters of the United States or Lotus. Lotus is a statutory language that determines which waters are protected under the Clean Water Act. It dictates where federal permits are required, where pollution limits apply, and where conservation and mitigation tools are made available. When that definition changes, it determines which waters receive federal protection and which are left to the states, sometimes leaving them with no protection at all. Following the Supreme Court's socket decision, federal jurisdiction has narrowed significantly, largely limiting Clean Water Act protections to relatively permanent waters and adjacent wetlands with a continuous surface connection. EPA and the Army Corps are again revising the WOTUS rule to reflect their interpretation of that ruling, and as a result, many more streams and wetlands that were previously covered are likely to fall outside federal protection. That matters because a narrower WOTUS definition doesn't just redraw jurisdictional lines. It removes federal conservation tools from the table. Fewer waters subject to Clean Water Act permitting means fewer opportunities for mitigation, less interagency and federal state consultation, fewer federal enforcement backstops, and less consistency in how and what waters are protected across state lines. The practical effect is that more responsibility shifts to the states, often without additional funding, tools, or capacity to replace what's been lost at the federal level. Some states may fill that void and protect some or all of the waters no longer under federal protection, but others will not, increasing variability and uncertainty for communities, ecosystems, and regulated entities alike. So, in 2025, WOTUS is about what waters are protected. It's not just a regulatory definition, but whether states are being equipped to carry the growing weight of receding federal protections, and what that means for water quality, economic development, and the framework the Clean Water Act was designed to support. How this all develops is definitely something worth keeping an eye on in 2026. Over the past hour, we've looked at how the US Supreme Court is reshaping environmental and administrative law, how NEPA review and public participation are being redefined across federal agencies, and how climate change is increasingly being treated as a question of legal rights and accountability. We've also explored the high stakes debates ahead, from the future of the endangerment finding and federal climate authority, to the narrowing of Clean Water Act protections, and the growing tension between federal and state roles as issues like data centers, energy infrastructure, and water resources move from policy debate to on-the-ground realities. Together, these developments point to a pivotal moment for environmental law. One where authority is shifting, long-standing tools are being reworked, or removed, and court and agencies are redefining the rules that will govern the next decade. As we head into 2026, the question isn't just what the law says, but how it will be implemented, who will bear responsibility, and what that means for communities, ecosystems, and action across a variety of environmental issues. Thank you all for listening to People Places Planet, and for joining us throughout 2025. We're grateful for your time, your engagement, and your interest in these conversations. If you'd like to learn more about any of the topics we discuss today, be sure to check out ELI's resources and upcoming events. We look forward to continuing this conversation with you in the year ahead. Thanks for listening to People Places Planet, the official podcast and the Environmental Law Institute. Our work wouldn't be possible without the support of people like you. If you'd like to learn more about what we do, attend one of our events, or support our work financially head to ELI.org.