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Supreme Court Hears Challenge to the EPA’s ‘Good Neighbor’ Plan

The justices will consider whether the number of participating states affects the ozone-reduction rule’s reasonableness.

By Jackson Coates  |  March 6, 2024

The U.S. Supreme Court recently heard arguments requesting a temporary block of a plan by Environmental Protection Agency to reduce air pollution that drifts across state lines.

The EPA’s 2015 “good neighbor” plan ordered 23 states to reduce their downwind ozone pollution. The current conflict arose when the agency rejected the plans of 21 states that proposed no changes to their emissions. Per the Clean Air Act, the EPA published federal plans for the states with insufficient plans, and for two that did not submit plans. The federal plans direct states to optimize the use of existing controls in power plants, install commonly used controls in power plants and other smaller sources of ozone, and use an emissions trading system.

Various appeals courts have stayed the EPA’s rejection of 12 state plans; however, the Court of Appeals for the District of Columbia Circuit did not. The court’s ruling impacted Ohio, West Virginia and Indiana, and those states appealed to the Supreme Court. The justices will decide only whether the states must comply with the EPA’s plan until the resolution of the lower court cases.

At the hearing, the states argued that there are only 11 states that currently comply with the EPA’s good neighbor plan, and that the EPA failed to consider the impact on states that could only partially comply. The states say that even partial compliance would benefit the environment because resulting reduction in ozone emissions would be diminished to a quarter of what the EPA initially anticipated. Chief Justice John Roberts described the decrease in emission reductions as “something new” for the EPA to consider. The states further argue that the unreasonable costs of compliance necessitate an emergency stay of the plan’s implementation.

Several justices did not share the states’ feeling of urgency. Justice Ketanji Brown Jackson described asking the court to decide this matter when the states had not yet lost the appeal as “fairly extraordinary.” Justice Sonia Sotomayor described the same issue as an attempt to “bypass the very court who’s going to make the substantive decision.” The EPA maintains that it anticipated some geographic changes in the plan and designed each federal plan to be workable if the number of included states changed. The agency also noted that it may succeed in some of the ongoing federal plan challenges across the country.

States must comply with the Good Neighbor plan by May 1, 2026. The court is expected to decide whether to temporarily block it by this summer.

Jackson Coates is an intern in NCSL’s State-Federal Relations Division.

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