Debates and scholarship over what the major questions doctrine is—and what it will mean for administrative law—have proliferated since the Supreme Court’s decisions in Alabama Realtors v. HHS, NFIB v. OSHA, and West Virginia v. EPA. The Association of American Law Schools (AALS) annual meeting last week was no exception, with multiple panels on the major questions doctrine. These included the Federalist Society’s annual faculty debate, moderated by my colleague Chris Walker. That conversation focused on whether the major questions doctrine is consistent with traditional tools of statutory interpretation and how the doctrine relates to constitutional values like the separation of powers and nondelegation, particularly in the West Virginia v. EPA case.

Yet none of the participants in these discussions paused to ask why the court might have chosen not to use traditional statutory interpretation tools to reach the same outcome. This has been an ongoing gap in conversations about West Virginia v. EPA since last summer, including among those who are critical of the decision and those who think the right outcome was reached but with the wrong analysis.

Answering this question is important. It is necessary to understand whether the doctrine—at least as the Supreme Court has thus far explained it—can possibly be squared with precedents like Chevron. It is also crucial for assessing how the doctrine might be deployed in future environmental and administrative law cases. So while I have many disagreements with the majority over how it ruled in this case and the arguments for a major questions doctrine more broadly, I will bite my tongue on these topics to simply address what may have been the court’s underlying motivation.

The majority’s decision to invoke the major questions doctrine, rather than use traditional tools of statutory interpretation, allowed the Justices to invalidate the Clean Power Plan without reviving federal nuisance lawsuits against fossil fuel companies—an outcome the court surely did not want. It’s difficult to know, of course, precisely what was in the minds of the Justices who signed onto the majority opinion. But this piece will explain why that result would have otherwise occurred and suggest how it may have influenced the majority’s use of the major questions doctrine.

Before delving into this issue, however, it is essential to correct a number of frequent misconceptions about how the Supreme Court applied the major questions doctrine in West Virginia v. EPA. First, the court did not find that EPA lacks authority to regulate greenhouse gas pollutants under the Clean Air Act. Some have suggested that the Supreme Court decided to apply the major questions doctrine in this case because it found the Clean Air Act was not meant to encompass climate change regulations. But no part of Chief Justice Roberts’ opinion questioned EPA’s ability to regulate greenhouse gas emissions from other parts of the Act. And while a few amici argued that the Supreme Court should revisit its 2007 decision in Massachusetts v. EPA, which held that greenhouse gases were air pollutants under the Act, the six Justices who joined the majority opinion showed no interest in pursuing such a result. As Justice Barrett acknowledged during oral argument, climate change and air pollution regulations are certainly within EPA’s wheelhouse. West Virginia v. EPA is thus distinct from cases like FDA v. Brown & Williamson or Alabama Realtors v. HHS that placed a lot of emphasis on the mismatch between the subject of the agency’s action and the authorizing statute.

Second, and importantly, the court studiously maintained that the statutory provision at issue in the case—section 111(d)—provides EPA with the authority to regulate greenhouse gas pollutants from existing power plants. And it did not interpret the specific statutory term “best system of emission reduction” to mandate onsite emission controls, which would have precluded the generation shifting approach in the Clean Power Plan.

Instead, the court relied on a set of non-textual factors—costs, political controversy, prior regulatory precedent, and negative legislative history—to conclude that generation shifting constituted a “major” policy matter.

So why not quash the Clean Power Plan through a textual analysis? The petitioners suggested such an approach using traditional tools of statutory interpretation: they argued that the phrase “best system of emission reduction” requires pollution control measures to be “onsite.” Yet as the Justices discussed at oral argument, EPA has many types of power plant regulations that are implemented across the industry rather than plant by plant, stack by stack. To find generation shifting invalid under this reasoning would create obvious problems for these approaches. Reading “best system of emission reduction” as mandating onsite reductions is also inconsistent with other Clean Air Act provisions like section 112, which governs hazardous air pollutants and contains different language to require what’s known as “maximum control technology” on a source by source basis.

Why not, then, find that the best reading of the text in section 111(d)—a “backwater” provision, as Justice Roberts called it—simply wasn’t meant to encompass generation shifting specifically or greenhouse gas regulation more broadly, and refuse to defer to EPA’s reading under Chevron? Why not go so far as to overturn Massachusetts v. EPA altogether? This is not a majority that seems particularly concerned with overturning precedent. Did the court simply refrain from doing so because the parties themselves hadn’t asked them to? Might the court be open to that possibility if they have the opportunity in a future case?

I don’t think so, and to explain why, I’m going to need to recount a little bit of Supreme Court history involving section 111(d) that has been largely absent from conversations about West Virginia v. EPA. Back in 2011, the Supreme Court heard a case called American Electric Power v. Connecticut, in which several states sued fossil fuel companies under the federal common law of nuisance. The goal of the suit was to force power plants to reduce greenhouse gas emissions through an injunction. In a unanimous opinion written by Justice Ginsburg, the court found that Congress had given EPA the authority under section 111(d) to regulate greenhouse gas emissions from power plants. Since Congress had addressed this issue through the Clean Air Act, it had displaced federal common law cases concerning climate change.

And thus we arrive at the crux of the Supreme Court’s problem in West Virginia v. EPA. If it held that section 111(d) does not apply to greenhouse gas emissions from power plants, the court would have overturned American Electric Power and allowed suits against fossil fuel companies to proceed under federal common law. There is plenty of evidence that such litigation would subsequently explode. Since American Electric Power, many cities and states have filed suits against fossil fuel companies under state tort law, given that federal common law is no longer available. A petition for certiorari is currently pending at the Supreme Court on whether these cases can proceed in state court. Notably, in their request for review, fossil fuel companies specifically cited to the Supreme Court’s decision in American Electric Power to argue that federal law must solely govern disputes over climate change.

The major questions doctrine, then, has allowed the Supreme Court to try to have it both ways, keeping the door shut on federal common law litigation by maintaining EPA’s authority under section 111(d) while removing the most promising regulatory approach to quickly and cost-effectively reduce greenhouse gas pollution. I find it no small irony that just over a decade after telling EPA it had Congressional authorization to reduce greenhouse gas emissions from power plants using section 111(d) the Supreme Court said well, wait a minute, not like that.

The potential implications of West Virginia v. EPA for litigation against fossil fuel companies suggest that the majority is unlikely to more aggressively restrict EPA’s authority to regulate greenhouse gases under the Clean Air Act. As things stand, these companies are going to have a very hard time arguing that Congress preempted state action on climate; it will be even more difficult to do so if the Supreme Court further erodes EPA authority.

Despite this small silver lining for those of us in environmental law who disagree with the decision, I’m less sanguine about the implications of the majority opinion for administrative law. By announcing the doctrine in a case where the court wanted to limit the specific form of a regulation, rather than regulation in a particular area (like evictions or tobacco products), the majority almost by default had to depart from the traditional tools of statutory interpretation that look to the law’s text, structure, purpose, and so forth. As a result, the opinion leaves the lower courts with a hodgepodge of vague factors to assess whether an agency action is major, which will prove difficult to implement in an objective way. There has already been an influx of recent efforts to characterize agency rules as major and unauthorized by Congress, so the Supreme Court may yet have the opportunity to revisit its explanation of what constitutes a major question. But given the opportunistic way the majority seems to have wielded the doctrine in West Virginia v. EPA, I remain skeptical that we will see a version that does anything other than serve as cover for the imposition of particular policy preferences.

Rachel Rothschild is an Assistant Professor at the University of Michigan Law School.