Obama-era trailer emissions standards reversed

November 15, 2021

Tyson Fisher


The Truck Trailer Manufacturers Association scored a major victory after a federal court of appeals reversed Obama-era emissions and fuel standards for trailers.

On Friday, Nov. 12, a District of Columbia Circuit Court of Appeals panel vacated all portions of a 2016 Environmental Protection Agency and National Highway Traffic Safety Administration rule that apply to trailers. Consequently, trailers will not have to adhere to stricter emissions standards.

EPA and NHTSA’s new standards went into effect in December 2017. It was the first fuel efficiency and emissions standards set for trailers.

In effect, trailers would likely require technologies like side skirts and automatic tire pressure systems in order to comply. In result, costs would significantly increase.

Less than a week before the rule went into effect, the Truck and Trailer Manufacturers Association filed a lawsuit against both agencies, claiming they overstepped their boundaries with the new rule. The court paused both agencies’ standards during litigation.

Is a trailer a ‘vehicle?’

At the heart of the dispute is whether a trailer is considered a vehicle.

The EPA regulates emissions for “motor vehicles.” It claims that it can regulate trailers as motor vehicles and trailer manufacturers as motor-vehicle manufacturers. The agency relies on the Clean Air Act, which defines “motor vehicle” as “any self-propelled vehicle designed for transporting persons or property on a street or highway.”

However, the court of appeals panel ruled that trailers are not self-propelled, keeping them outside of the EPA’s emissions regulatory jurisdiction.

The EPA also argued that the court should focus on the “designed for transporting persons or property” portion of the definition. Specifically, it claims that “the tractor-trailer as a whole should be considered the pertinent vehicle” because a tractor “cannot accomplish its intended purpose” unless the tractor is pulling the trailer. The court was not convinced.

“But tractors can carry people and things without trailers attached,” the opinion states. “As anyone who has spent any time on a highway knows, they often do. So a tractor without a trailer can still accomplish what it is ‘designed for.’ That makes a self-propelled tractor a ‘motor vehicle’ long before a trailer is ever attached.”

The EPA additionally argued that trailer manufacturers are motor-vehicle manufacturers. It stated that “because a trailer attached to a tractor can be imagined as a ‘tractor-trailer’ (true), a trailer manufacturer is ‘engaged in the manufacturing’ of a motor vehicle (false),” the court ruled.

Regarding NHTSA’s rule, it can regulate fuel efficiency for “an on-highway vehicle with a gross vehicle weight rating of 10,000 pounds or more.”

Unlike EPA’s statute, the term “vehicle” is not defined. Based on context, the court found that “vehicle” in this case is limited to machines that use fuel, not necessarily consume fuel.

Judge argues NHTSA’s rule is legal

Circuit Judge Patricia Millett filed a dissent to the findings of NHTSA’s rule. Judge Millett argued that “vehicles” should be interpreted to include trailers.

Specifically, Millett states that “vehicle” is defined in other parts of pertinent federal law to include trailers. For example, the Motor Vehicle Information and Cost Savings Act defines “motor vehicle” to include “vehicles” that are “driven or drawn by mechanical power” (emphasis Millett’s).

With “vehicle” defined, Millett turned to the legislative purpose behind the regulation. In this case, fuel efficiency was the target. Considering tractor-trailers consume significantly more fuel than tractors alone, Millett argued, it is likely trailers should be factored into the equation. LL

Tyson Fisher joined Land Line Magazine in March 2014. An award-winning journalist and tireless researcher, his news reports, features and blogs bring depth to our editorial content, backed with solid detail. Tyson is a lifelong Kansas Citian.