In a 2014 ruling, an appeals court decided that the Environmental Protection Agency "properly [put] the horse before the cart" in coming up with mandates to limit power-plant emissions of mercury and other pollutants. The Supreme Court today overturned that ruling, blocking a key White House environmental initiative because it said the agency didn't do due diligence in figuring out how much it would cost the industry, the New York Times reports. Any regulations arising out of the Clean Air Act are required to be "appropriate and necessary," and industry groups, in addition to 20-plus states, had argued that the EPA didn't carry out the proper cost-benefit analysis that would show the impact of such regulations. Justice Antonin Scalia wrote for the majority in the 5-4 ruling, with justices Elena Kagan, Ruth Bader Ginsburg, Stephen Breyer, and Sonia Sotomayor dissenting, reports the Washington Post.
The regulations, which the AP notes started to take effect in April, required coal- and oil-fired power plants to put in special "scrubbers" to get rid of pollutants, especially mercury emissions, which can be particularly toxic to kids and unborn children, the Wall Street Journal notes. The EPA says it did carry out the cost-benefit analysis its critics mention, even though it notes it wasn't obligated to, since public-health concerns should hold sway over financial ones. Both sides agree the regs will cost the industry about $9.6 billion—but the EPA says doing so will result in "between $37 billion and $90 billion in benefits and prevent up to 11,000 premature deaths annually," per the Hill, while industry groups came up with their own benefits estimate of $6 million, the Times reports. Some good news: To comply with the EPA, most power plants have already closed shop, made changes, or put in place plans to do so, the Hill reports. (Read more US Supreme Court stories.)