A federal judge barred the Biden administration from using its interim revised social costs of greenhouse gas pollution in crafting regulatory policy on Friday. The ruling by Trump-appointee James Cain in a federal court in Louisiana sided with Republican attorneys general in ruling that using the administration’s interim cost calculations for CO2, methane, and nitrous oxide could reduce states’ royalties. “The social cost of carbon guides the stringency of climate policy,” Michael Greenstone, a professor at the University of Chicago, told the AP. “Setting it to near-zero Trump administration levels effectively removes all the teeth from climate regulations.” The ruling was also criticized by administrative law experts. (Ruling: AP, E&E News, CNN, The Guardian, Mother Jones, Reuters, Politico Pro $; Regulatory experts: E&E $; SCC explainer: The Conversation)