The Supreme Court's conservative majority is likely to restrict the Biden administration's environmental efforts, specifically the U.S. Environmental Protection Agency's plan to reduce cross-state air pollution, impacting public health and environmental policies. In short:The "good neighbor" plan aimed to cut ozone pollution affecting downwind states is under threat, with a decision expected by June. The plan's suspension could delay pollution control efforts, affecting states reliant on upwind pollution reduction. Why this matters:The potential blocking of the EPA's air pollution plan brings to light the struggle and intricate balance between federal authority and state responsibilities in managing air quality. Learn more about air quality and respiratory health from Kristina Marusic's reporting in our series: Breathless.