Twenty-three US states, led by New York & California, have sued the EPA over its repeal of the 2009 Endangerment Finding. The finding served as the legal basis for federal climate regulations. The lawsuit argues the agency acted unlawfully. The case is expected to reach the Supreme Court. The EPA claimed the revocation would save $1.3 trillion, but environmental groups project it will increase gasoline prices by up to 9% & add over $3 billion in annual fuel costs by 2035.