Alabama Attorney General Steve Marshall joined a coalition of 25 states led by West Virginia and Indiana urging the U.S. Supreme Court to issue an emergency stay on the implementation of the U.S. Environmental Protection Agency’s recently-released new rule on existing coal-, natural gas- and oil-fired power plants.

The action follows the U.S. Court of Appeals for the District of Columbia Circuit’s refusal last week to block the rule. That rule would force power plants fueled by coal or natural gas to capture smokestack emissions using currently unworkable technologies or shut down. It would regulate those plants under the Clean Air Act by imposing more stringent emissions standards.