In a 5-4 ruling, the Supreme Court ruled that the Environmental Protection Agency (EPA) had not adequately considered the costs of its regulations before enacting them. Limits finalized in 2012 as part of the Clean Air Act on toxic air pollutants proved to be a prohibitive cost on coal utility plants. They were also a main feature in the Obama administration’s environmental policies.
The case, Michigan v. EPA, centered on the first ever limits on mercury, arsenic, and acid gases emitted by coal-fired power plants. While the EPA had estimated the new rules would cost $9.6 billion, placing it among the costliest regulations ever instated.
Prior to the ruling, the head of the EPA Gina McCarthy had said she felt confident the Supreme Court would rule in their favor. However, were that not to be the case, she said:
But even if we don’t [win], it was three years ago, most of them are already in compliance, investments have been made, and we’ll catch up. And we’re still going to get at the toxic pollution from their facilities.
With most coal plants already in compliance, the ruling does little to slow emission curbs in the coal industry. Regulations on interstate air pollution were already upheld last year by the Supreme Court, ensuring that most utilities will need to control future pollution regardless of the new ruling. Furthermore, in the majority opinion, written by Justice Scalia, the Court ruled that the EPA could reconsider the regulations with better cost assessments before reinstating such rules.