In a unanimous opinion authored by Justice Nielsen, the court ruled that the district court erred by applying a policy-balancing test to negate a broad statutory duty to operate safe equipment on roadways. The court also held that the lower court improperly excluded expert testimony regarding the dangers of underride crashes and the potential for injury prevention.
The case stems from a 2017 collision in Parley’s Canyon involving a Volkswagen Jetta driven by Raul Lopez and carrying passenger Emilio Martinez-Arroyo. Lopez, traveling at approximately sixty miles per hour, struck the rear of a utility trailer owned by Ron J. Peterson Construction, Inc. (RJP). The trailer, which was hauling a large forklift, lacked underride protection. The Jetta’s passenger compartment slid beneath the trailer, killing both occupants instantly.
Yesneiri Maldonado-Velasquez, Martinez-Arroyo’s widow, sued RJP for negligence. She argued that the company operated its equipment unreasonably and that the trailer’s lack of underride guards made the crash far deadlier than it needed to be. She sought to introduce expert testimony on underride dangers and how such guards might have reduced the extent of injury.
The district court had granted summary judgment on the enhanced-injury claim, ruling that RJP had no duty to upgrade the trailer beyond minimum federal safety standards. The court reasoned that Utah Code section 41-6a-206, which states that federal motor carrier regulations supersede conflicting state provisions, precluded any higher state-law obligation.
The Utah Supreme Court rejected this interpretation, surveying the four strains of federal preemption and concluding that Federal Motor Carrier Safety Regulations establish only a conflict preemption scheme. The court noted that federal rules are explicitly "minimum standards" and do not prevent states from imposing more stringent requirements so long as full compliance with both is possible.
Justice Nielsen wrote that federal regulations in this area function as a floor, not a ceiling, citing decisions from the Fourth and Sixth Circuits, as well as a Northern District of Indiana ruling, holding that state laws imposing safety requirements beyond the federal baseline are not preempted. The court stated, "State law can impose a level of duty exceeding federal motor carrier regulations because it is possible to adhere to such a standard without making it impossible to comply with that federal floor."
The court also criticized the district court’s use of the *Jeffs* policy analysis framework. The Supreme Court held that *Jeffs* factors are necessary only when a party seeks to establish a previously unrecognized duty for a category of cases. They do not apply when a plaintiff invokes a categorical duty already recognized under Utah law, such as the duty under Utah Code section 41-6a-1601(1)(a)(i) to not operate a vehicle in an unsafe condition that may endanger any person.
RJP argued that any error was harmless because the jury ultimately found RJP bore no fault for the collision. The court flatly rejected that argument, noting that the jury reached its verdict without hearing the excluded expert testimony. The court stated, "This additional evidence of RJP's alleged negligence may affect a jury's assessment of, well, RJP's negligence."
The ruling reinforces that the multi-factor policy analysis for duty recognition is a tool for novel duty questions only. For practitioners, the decision signals that federal motor carrier compliance does not inoculate defendants from state negligence liability; meeting the federal floor is a starting point, not an ending one.
The case now returns to the Third District Court in Summit County for a new trial. The appeal was taken directly from the district court, where District Judge Richard E. Mrazik had presided. The Supreme Court heard oral argument on December 8, 2025, and issued its opinion on April 16, 2026.