ELR Citation: 51 ELR 20196
No(s). 16-1430 (D.C. Cir. Nov 12, 2021)

The D.C. Circuit granted a trade group's petition to review a 2016 rule issued by EPA and the National Highway Traffic Safety Administration that set greenhouse gas emissions and fuel efficiency standards for medium- and heavy-duty engines and vehicles. The group challenged the agencies' authority to regulate heavy-duty trailers under the rule. The court found that trailers were not motor vehicles under the CAA because they had no motor and were not self-propelled. It further found that trailers were not subject to the fuel efficiency improvement program under the Energy Independence and Security Act because they did not use fuel and thus did not have fuel economy. The court therefore granted the petition and vacated all portions of the rule that applied to trailers.