The Supreme Court declined Monday to take up an appeal from conservative states challenging California’s ability to establish strict vehicle emission rules that effectively set the standard for the rest of the nation.

The Supreme Court agreed Monday to examine California’s authority to set strict vehicle emissions standards, potentially affecting nationwide environmental policy and automotive industry practices. The case focuses specifically on whether fuel companies and other business interests have legal standing to challenge California’s regulations,

The Supreme Court says it will take up a business-backed appeal that could make it easier to challenge federal regulations, acting in a dispute related to California’s nation-leading standards for vehicle emissions.