California has established a requirement that 17% of a given manufacturer’s new vehicle sales in the state be “zero-emissions vehicles” by model year 2023, increasing to 35% in 2026 and then in steps to 100 percent by 2035. The ostensible purpose is a decrease in vehicle carbon dioxide emissions, but with the technology currently available such reductions can be achieved only with a decline in per-mile fuel consumption.

Accordingly, the California mandate is a de facto fuel economy standard more stringent than the federal standards as promulgated by the Department of Transportation. This state-level fuel economy standard clearly is illegal because the Energy Policy and Conservation Act specifically prohibits state-level automobile fleet regulations “related to” fuel economy.