What was the ruling?
The decision states that the EPA’s actions in a 2015 rule, which included caps on emissions from power plants, overstepped the agency’s authority to regulate greenhouse gas emissions.
“Capping carbon dioxide emissions at a level that will force a nationwide transition away from the use of coal to generate electricity may be a sensible ‘solution to the crisis of the day,’” the decision reads, “But it is not plausible that Congress gave EPA the authority to adopt on its own such a regulatory scheme.
Only congress has the power to make “a decision of such magnitude and consequence,” it continues.
This decision is likely to have “broad implications” says Deborah Sivas, an environmental law professor at Stanford University. Not only is the court constraining what the EPA can do on climate policy going forward, she adds. This opinion “seems to be a major blow for agency deference,” meaning agencies beyond just the EPA could face limitations in the future.
The ruling, which is the latest in a string of bombshell cases from the court, fell largely along ideological lines. Chief Justice John Roberts authored the majority opinion, and he was joined by conservatives, including Justices Samuel Alito, Amy Coney Barrett, Neil Gorsuch, Brett Kavanaugh, and Clarence Thomas. Justices Stephen Breyer, Elena Kagan, and Sonia Sotomayor dissented.
What is the decision all about?
The main question in the case was how much power the EPA should have to regulate carbon emissions and what it should be allowed to do to accomplish that job. That question was raised by a 2015 EPA rule called the Clean Power Plan.
The Clean Power Plan targeted greenhouse gas emissions from power plants, requiring each state to make a plan to cut emissions and submit it to the federal government.
Several states and private groups immediately challenged the Clean Power Plan when it was released, arguing it was an overreach from the agency, and the Supreme Court put it on hold in 2016. After a repeal of the plan during Donald Trump’s presidency and some legal back-and-forth, a Washington D.C. district court ruled in January 2021 that the Clean Power Plan did fall within the EPA’s authority.