The Supreme Court has overturned Chevron deference, a precedent set in 1984 when the Court ruled in Chevron U.S.A. Inc. vs. Natural Resources Defense Council, Inc that if a statute was ambiguous and Congress had not explicitly addressed an issue, then courts must defer to the agency’s approach to addressing it as long as the agency provides “a permissible construction of the statute.” The new precedent-setting ruling voids this decision, diminishing federal agencies’ powers, influencing pending and established environmental regulations, and creating a powerful new argument for regulatory disputes, including in energy-related industries and areas. Ultimately, this ruling will send energy companies and their opponents to court, where their attorneys and representatives of the federal and state governments, and environmentalist NGOs will bear the weight of litigation.