US auto regulators can now ignore costs when setting fuel economy standards

US auto safety regulators have changed how they interpret the law for setting fuel economy standards. They say they no longer have to consider the costs to carmakers or consumers when setting these rules.

For decades, fuel economy rules were a negotiation between environmental goals and industry costs. This change means regulators can set much stricter standards without having to justify the economic impact on car manufacturers or buyers. It removes a major legal constraint that has limited how quickly the US could push for more fuel-efficient vehicles.