Editor’s Note (6/28/24): On Friday the Supreme Court overruled the 1984 case that had established Chevron deference. “Agencies have no special competence in resolving statutory ambiguities,” the new opinion read. “Courts do.”
The Supreme Court is set to rule as soon as Wednesday on a seemingly tedious pair of cases that question who should pay for congressionally mandated observers on fishing boats: the owners of the boats or a federal agency. But far from being small fish, the opinions may rejigger the balance of power among the branches of government and weaken the role of science in policymaking.
These cases target a long-standing precedent called Chevron deference, which determines how courts evaluate a given federal agency’s interpretation of congressional statutes that guide that agency’s actions. These statutes often contain accidental or intentional ambiguities. And for the past 40 years, agencies have had the leeway to interpret those ambiguities because courts have recognized that these offices are staffed by people with special training and scientific expertise.
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But legal experts say that Chevron deference will almost certainly change—the only question now is whether the Supreme Court will completely overturn the principle or merely narrow it. And the Court’s decision will ripple far beyond the fishing community. The ruling could affect how medication is approved and what pollutants are regulated; it challenges the authority of a host of agencies, including the Food and Drug Administration, the Occupational Safety and Health Administration and the Environmental Protection Agency, where Chevron deference began.
“Rolling back Chevron is going to create a huge paradigm shift in how the government works and even how Congress legislates,” says Andrew Twinamatsiko, director of the Health Policy and the Law Initiative at Georgetown University.
Chevron deference gets its name from a 1984 Supreme Court case that hinged on how the EPA chose to interpret Congress’s Clean Air Act. Under the administration of President Ronald Reagan, the EPA had decided to define the term “source” in a way that would allow a host of new industrial projects to evade pollution emission regulation, says David Doniger, an attorney at the Natural Resources Defense Council (NRDC), who argued—and lost—that case.
In its original opinion for the 1984 case, the Court established two principles for evaluating an agency’s actions when it fulfills instructions from Congress. If the relevant statute was clear, the case determined, the agency would have to abide by it. If the statute was ambiguous, a court would have to defer to the agency’s reasonable interpretation of what it might mean—otherwise the judicial branch would risk overstepping its mandate and entering the realm of policymaking. In the situation Doniger and the NRDC had objected to, the court decided, the Clean Air Act was ambiguous, and the EPA had made a reasonable interpretation. So the agency’s relevant projects were not subject to the regulations.
At the time, it was an unremarkable reminder of judicial restraint that had been the norm for a century, Doniger says. “It really wasn’t breaking new ground,” he says. “But it became a very concise restatement of that approach.” In the decades since the decision, the Chevron opinion has been cited more than 16,000 times in courts across the country.
Even Doniger has come to appreciate the policy. A particularly important feature of Chevron deference, he says, is its nonpartisan nature. “It is a neutral principle,” Doniger says. “It lets conservative administrations cut back on the scope of these laws, and it lets liberal administrations do more with them.”
A Threat to Scientific Expertise
Judicial deference to agencies’ expertise is crucial to how U.S. medical and environmental regulation, in particular, currently works. For example, the FDA currently uses its discretion to loosen approval requirements for treatments of rare diseases, such as by permitting historical records to substitute for a control group in a clinical trial, says Reshma Ramachandran, an assistant professor at the Yale School of Medicine, who has a background in public policy. And the agency’s ability to regulate new products—such as vaping systems and genetic tests marketed directly to consumers—can rely on the ambiguity in terms such as “medical devices” in legislation from Congress.
Ramachandran worries that if Chevron deference falls, the FDA will become more cautious out of fear of being taken to court and losing. “I think the government agencies are just going to be much more hesitant to follow the science and instead might make decisions based on the political and legal landscape,” she says. New treatments might take longer to be approved, and on the other end of the spectrum, people could be exposed to dangerous or misleading products that were able to evade regulation, she worries.
Doniger cites the EPA’s regulation of carbon emissions as pollutants and OSHA regulations that targeted the spread of COVID in workplaces early in the pandemic as examples of the sort of situation in which Chevron deference can allow agencies to take the lead on topics that are firmly within their territory but about which Congress has yet to create detailed legislation.
Since the development of Chevron deference, Congress and federal agencies have settled into a pattern that works, experts say. Congress writes legislation—which sometimes remains in place for decades—with ambiguities, and the agencies that know the relevant topics better turn that legislation into meaningful and practical policies.
“Congress doesn’t have the time or expertise to fill in the details for thousands of regulations, and it’s hard to anticipate the twists and turns of the future and exactly what [lawmakers] need to spell out specifically,” says Dena Adler, a senior attorney at New York University’s Institute for Policy Integrity. Agencies use their expertise to turn broad-brush statutes into nitty-gritty policies, and the courts intervene only in extreme circumstances.
Of course, that’s assuming Congress passes legislation in the first place, which is becoming increasingly difficult amid deep partisanship. “Since Congress is so gridlocked, we’re often using existing laws to meet novel challenges,” Adler says. Without Chevron deference, she fears courts may reject agencies’ attempts to fit new issues or technologies into the scope of existing laws. “I think this decision could have real implications for agencies’ ability to tackle the problems of the day like climate change,” she says. The Clean Air Act specifically directed the EPA to incorporate chemicals that would later be determined to be air pollutants, but not all legislation includes this kind of future-proofed language.
Blurring the Lines of Agencies’ Authority
Chevron precedent isn’t the only source of agencies’ authority, particularly on technical matters. In some situations, legislation does explicitly order a given agency to make certain evaluations, and agencies’ actions in these circumstances should be respected even without Chevron deference, Adler says. And other legal principles exist that support reasonable scientific judgements made by agencies, she notes. But Adler worries these principles may come under fire anyway as small-government advocates seek to blur the lines between such situations and those covered by Chevron deference, which applies exclusively to interpretations of congressional statutes.
Regardless of whether Chevron is overturned or weakened, federal agencies will likely face a spike in lawsuits as adversaries feel out the boundaries of the Supreme Court’s decision, experts say. Challenges that succeed will force agencies to start fresh on a given issue after federal workers already spent years developing its related rule. Even unsuccessful challenges pull agency resources from other work, says Emily Hammond, a professor of law at the George Washington University. “It’s a huge distraction, and it’s also years and years of work,” they say. “It is a big disruption to have a rule overturned.”
The less deference agencies expect to have in court—and the more often they expect to end up there—the more limited policies are likely to be, experts agree. Rather than using the full powers of the statutes Congress has written, agencies will likely err on the side of caution.
Cultivating hesitancy within federal agencies isn’t necessarily antiscience, but it’s hardly proscience either. “Certainly that weakens the capacity of the government to respond when science reveals a threat to people’s health or people’s lives,” Doniger says.
Weakening Chevron deference “doesn’t actually deny that COVID is transmitted in the workplace or that air pollution is causing cancer or causing climate change; it just makes it much harder for the government to do anything about it,” he says. “It comes down to whether the government can protect you.”