Overview

• The National Highway Traffic Safety Administration's rule requires an average fuel economy of 50.4 mpg by 2031.
• Republican-led states claim the rule exceeds the agency’s authority and is legally flawed.
• Industry groups, including the American Petroleum Institute, have joined the legal challenge.
• Critics argue the rule will increase vehicle costs and strain the electric grid.
• The Biden administration defends the rule, citing benefits of reduced pollution and fuel savings.