Earlier this week the Supreme Court voted 5-4 to stay enforcement of the EPA’s Clean Power Plan, granting a request by two dozen states and various industry groups to delay all of the rule’s deadlines while litigation proceeds. The decision comes after states including West Virginia and North Carolina filed lawsuits back in October 2015 against the Obama administration’s Clean Power Plan, immediately following its publication.

The Clean Power Plan, which is intended to curb greenhouse gas emissions from power plants, is the primary mechanism the US would use to reach its carbon footprint reduction target pledged at the U.N. climate talks in Paris in December 2015. The plan requires states to reduce carbon dioxide emissions from generation sources 32% by the year 2030, and compliance with the new rule isn’t required until 2022. However, states must submit their plans to the EPA by September 2016 or seek a two-year extension.

A press release from The White House stated they disagree with Supreme Court’s decision and, “even while the litigation proceeds, EPA has indicated it will work with states that choose to continue plan development and will prepare the tools those states will need.”

Wake Forest University Law Professor and CEES faculty affiliate Sidney Shapiro says the Supreme Court’s decision is highly unusual in a number of ways. Since the rule itself isn’t slated to take place right away, “it gives the states a very long period to prepare, so the immediate impact on the states while the litigation is ongoing is fairly minor.” And despite that, the Supreme Court voted 5-4, “which might suggest some considerable hostility by the conservative justices.” The stay in unprecedented move to halt regulations while an issue is still under review by an appeals court.

Over one dozen other states and the National League of Cities filed court papers backing the rule.

Vanessa Zboreak, a CEES faculty affiliate who teaches Sustainability Law and Policy at Wake Forest University, says the states already committed are likely to continue planning while the substantive litigation over the rule plays out.

According to Zboreak “The bigger issue here is what this signals to other countries, particularly developing countries, about America’s potential to renege on an agreement. Without the Clean Power Plan, it’s possible that we would meet our Paris commitments, but it certainly seems to indicate that it’s not a priority for the U.S.”

With President Obama leaving office in January 2017, the Supreme Court’s action also enables the next president to decide whether or not to continue defending the regulation.