"The decision was in line with several Supreme Court decisions in recent years that reined in federal agencies by striking down regulations on the grounds that agencies had usurped power from Congress and the judicial branch. West Virginia led a coalition of Republican-leaning states and coal producers that asked the Supreme Court to weigh in and clarify the limits of the Environmental Protection Agency’s authority, raising broader questions about how far the regulatory authority of federal agencies extends. The coalition said powerful and wide-reaching policies should come from Congress, not agency-level regulators."