The Environmental Protection Agency: Federal Regulatory Power vs. State Autonomy

Since its establishment in 1970, the Environmental Protection Agency (EPA) has served as a federal body dedicated to protecting the environment. Throughout its history, the EPA has championed climate initiatives through the implementation of various regulations and provisions. Most significantly, the EPA has gained authority to fight against climate change, specifically air pollution, through the Clean Air Act. The Clean Air Act, established in 1970 and later amended in 1990 to reflect changing times, was created to give the EPA the jurisdiction to regulate air pollutants, specifically greenhouse gas emissions, and to set and achieve National Ambient Air Quality Standards (NAAQS) through state implementation plans (SIPs). State Implementation Plans are documents and regulations that are utilized by states to enforce the NAAQS and to honor the requirements set in the Clean Air Act. Past Supreme Court orders, such as Massachusetts v. EPA, have highlighted the success of the Clean Air Act and its regulatory power. Conversely, current Supreme Court proceedings, most notably the Ohio v. EPA case, have contradicted the precedent regarding the scope of power designated to the EPA through the Clean Air Act.

The case of Massachusetts v. EPA (2007) was a significant Supreme Court case that helped clarify the EPA’s authority under the Clean Air Act. The lawsuit arose when Massachusetts and 11 other states decided to sue the EPA for stronger regulation of greenhouse gas emissions, specifically emissions from motor vehicles. The 11 states span large geographical distances and include Massachusetts, California, Connecticut, Illinois, Maine, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont, and Washington. The states argued that the EPA failed in its role to set and enforce “emission standards for air pollutants from motor vehicles that… play a role in pollution that could be reasonably expected to endanger public health or welfare” and therefore the EPA is in violation of the Clean Air Act’s 202(a)(1) provision. Furthermore, the Clean Air Act defines an air pollutant as any combination of agents that enter the ambient air while “welfare” is defined broadly as  “effects on weather and climate”. The case of Massachusetts v. EPA emphasized the importance of interpreting the Clean Air Act in a way that allows the EPA to fulfill and prioritize its role of addressing greenhouse gas emissions and enforcing the NAAQS.

Out of the 11 states, Massachusetts specifically claimed that the lack of emissions standards for vehicles resulted in the loss of their coastline as a result of higher sea levels, using this argument as an example of concrete injury caused by the EPA’s negligence. The state additionally argued that these changes were the result of global warming. In response to the lawsuit, the EPA claimed that it lacked the regulatory authority over greenhouse gasses and that setting emissions standards for vehicle emissions was unnecessary. The Supreme Court ruled in favor of Massachusetts in a close 5-4 decision. The majority opinion claimed that the environmental claims employed by the states had standing because of Massachusetts’ “stake in protecting its quasi-sovereign interests as a state” and that the Clean Air Act is written with “capacious” and “sweeping” language and therefore includes that ubiquitous greenhouse gas emissions should be overseen by the EPA if they are found to endanger public health or welfare. The dissenting opinion expounded that the states did not have standing to sue because the environmental evidence provided was not concrete and too speculative. However, under the parameters set by the majority ruling, it was legally established that the EPA is responsible for regulating greenhouse gas emissions.

While the Massachusetts v. EPA case set a precedent that empowered the EPA to expand its regulatory power over harmful greenhouse gas emissions, the Ohio v. EPA contrarily challenges the extent of the EPA’s authority. Ohio v. EPA was decided on June 27, 2024. In this case, the 5-4 majority opinion of the Supreme Court ordered the suspension of the EPA’s legal proceedings concerning the Good Neighbor Plan. The Good Neighbor Plan, established in 2015, is designed to assist states in complying with the “Good Neighbor” provision of the Clean Air Act, which requires that emissions from one state do not significantly contribute to air quality problems in downwind states. The 2015 Plan required states to submit different State Implementation Plans to comply with new standards. It targets ozone pollution by reducing nitrogen oxide (NOx) emissions from power plants and industrial sources. In Ohio v. EPA, Ohio and other states argued that the EPA overstepped its authority by rejecting their state implementation plans (SIPs) and imposing a Federal Implementation Plan (FIP) to regulate nitrogen oxide (NOₓ) emissions. The states that did submit their SIPs claimed that they were not required to adopt measures to control their emissions in order to observe the Good Neighbor Provision because they “were not linked to downwind air-quality problems or they could identify no additional cost-effective methods of controlling the emissions beyond those they were currently employing.”  The regulation of these emissions is key in achieving National Ambient Air Quality Standards (NAAQS) in downwind states, which is one of the main goals of the Clean Air Act. In 2022, the EPA disapproved 23 of the states’ State Implementation Plans and wanted to bind all of these states under one Federal Implementation Plan. Federal Implementation Plans are air quality plans that are developed by the EPA. The goal of an FIP is to maintain the NAAQS and is developed if a state “fails to submit a complete implementation plan, or if EPA disapproves a plan as not meeting Clean Air Act requirements.”

The EPA’s plan relied on the assumption that upwind States would also adopt measures towards reducing emissions. However, commenters argued that upwind states could eventually abandon the FIP, a concern the EPA failed to address. Therefore, the Supreme Court determined that the state’s argument “that the EPA’s action was arbitrary or capricious because the agency failed to offer a satisfactory explanation for its action, including a rational connection between facts found and the choice made, and ignored an important aspect of the problem” had standing. Furthermore, the Supreme Court concluded that the EPA’s Federal Implementation Plans problem was the method the EPA used to unilaterally determine which emissions were significant contributors to states’ difficulties in achieving the ozone standards. The EPA claimed that their rule would “lead to significant reductions in carbon pollution over the next two decades… equivalent to preventing the annual emissions of 328 million gasoline cars.” By challenging the Good Neighbor Plan, the Ohio v. EPA case highlights the growing tension between state autonomy and federal authority, threatening the EPA’s ability to enforce consistent environmental standards that are critical to nationwide air quality.

The differences between Massachusetts v. EPA and Ohio v. EPA reflect an ongoing debate over the extent of federal regulatory authority regarding the environment. While Massachusetts v. EPA affirmed the EPA’s obligation to regulate greenhouse gas emissions under the Clean Air Act, Ohio v. EPA highlighted a shift towards limiting the agency’s ability to enforce federal standards (NAAQS). The Supreme Court’s decision in Ohio v. EPA weakens the EPA’s control over air pollution and greatly contrasts the Massachusetts v. EPA case, where the EPA’s role in protecting public health and welfare was expanded. The Clean Air Act was written with “sweeping” language to give the EPA the authority to address environmental challenges on a greater scale. The Clean Air Act therefore gives the Good Neighbor Plan merit because the Plan seeks to mitigate air pollution, including NOx which contributes to greenhouse gases. In Massachusetts v. EPA, the Court interpreted the CAA in a way that highlighted environmental health. In Ohio v. EPA, the Court should have upheld this prioritization as the precedent had been set by Massachusetts v. EPA. Ultimately, it is essential to find a balance between a state’s autonomy and federal authority, but the EPA must prioritize environmental protection, as demonstrated in Massachusetts v. EPA.

Edited by Audrea Elle Chen