The Supreme Court is allowing a challenge to President Barack Obama's new environmental regulations to go forward, potentially posing risks for the EPA's climate change prevention plans. Earlier today, the court accepted six petitions from the US Chamber of Commerce, the state of Texas, and others. But of those petitions, only a single question will be considered: "Whether EPA permissibly determined that its regulation of greenhouse gas emissions from new motor vehicles triggered permitting requirements under the Clean Air Act for stationary sources that emit greenhouse gases." Three further petitions were rejected.

In short, the Supreme Court will be examining whether by deciding to regulate car emissions, the EPA gave itself the power to regulate institutions like power plants. As elucidated by the SCOTUS Blog, this significantly narrows the questions, and some have taken this as a good sign. "Let's be clear about what the Supreme Court did today," says the Natural Resources Defense Council in a statement. "The court rejected pleas by big polluters and a small group of states to review the EPA's authority to limit greenhouse gas emissions from vehicles and other sources when they endanger public health or welfare." The question it took up, however, could affect the EPA's attempts to put limits on how much carbon coal and natural gas plants could release.

This challenge follows a previous ruling, in which the Supreme Court found that carbon was a pollutant that could fall under the Clear Air Act's purview. Since then, Obama has put forward a plan to encourage renewable energy and rein in pollution from fossil fuels. Its projected benefits, however, aren't necessarily clear. The plan has been criticized for its potentially ineffective regulations and its reliance on minimally tested carbon capture technology, which is meant to help coal plants go clean. According to Reuters, arguments for the program's legality are likely to take place in early 2014, with a decision expected by the end of June.