The U.S. Supreme Court Monday said it won't consider a challenge to California's low carbon fuel standard, which critics say will lead to higher fuel prices in the Golden State.
The controversial 2007 rule, the only one of its kind in the country, requires fuel producers to reduce the carbon footprint of their products over the entire life cycle of the fuel, including the greenhouse gases generated in producing, refining and transporting the fuel.
The goal is to encourage biofuels, electric vehicles and other alternatives that account for less greenhouse gas emissions.
A coalition of energy, farm and trade groups sued, saying the rule illegally discriminates against fuel produced outside of the state. California, however, contends that some of the fuels with the lowest carbon-intensity scores came from out of state.
A federal trial judge blocked the rule in 2011, but a federal appeals court reversed that ruling last year. The Supreme Court let that ruling stand without comment.