On Monday, the US Supreme Court heard oral arguments regarding the landmark West Virginia v. Environmental Protection Agency case. After the hearing concluded, a variety of legal analysts provided differing opinions on how the Supreme Court justices would view the case as presented by each side and it was not entirely clear how the justices would rule judging by their questioning of the arguments.  

Depending on how the justices decide the case, the ruling could not only restrict EPA’s options for addressing carbon dioxide emission reductions going forward, but it could also limit agency powers that extend well beyond emissions regulations. The petitioners, led by West Virginia, North Dakota and North American Coal had asked the court to find that EPA’s past rulemaking violated the major questions doctrine, which says that courts can’t defer to agency discretion to interpret the law on issues of significant economic or political impact. Overall, it was unclear whether a majority of the justices would get behind that specific argument.

Although the Biden administration has said it plans to draft a brand-new power plant rule, the justices yesterday appeared unlikely to find that the West Virginia case had arrived at the Supreme Court too early to make a decision while EPA completes the rulemaking process. The court is likely to rule by their June recess, when decisions are traditionally announced as their term ends.