A plaintiffs’ expert is qualified to testify about whether the deactivation switch in a Ford F250 truck was negligently designed, the South Carolina Supreme Court has ruled.

The high court’s ruling reverses a finding by the intermediate appellate court that a $41,000 products liability verdict should be overturned and the trial court should have granted a directed verdict.

Plaintiffs 5 Star Inc., is a lawn maintenance and pressure washing company owned by Stan Shelby. Nine years ago, 5 Star purchased a used 1996 Ford F-250 pickup up truck, which Shelby parked one weekend in his company’s warehouse. During the weekend, a fire destroyed the truck and severely damaged the warehouse. A fire investigator determined that the engine compartment of the truck was the likely origin of the conflagration.

According to Justice John Kittredge’s opinion, the plaintiffs’ expert testified that the deactivation switch was designed to be constantly on even when the ignition was off; the two-ampere fuse switch was protected by a 15-ampere fuse, allowing the switch to overheat and start a fire long before the fuse would ever blow; and the switch was separated only by a thin membrane from the flammable hydraulic brake fluid.

Plaintiffs’ expert Leonard Greene is a licensed electrical engineer who has testified about the origin of fires, electrical engineering and defective products between 50 and 100 times for both plaintiffs and defendants. Greene was qualified as an expert because he has “worked for companies that designed component parts—such as integrated circuits and timers—for use in vehicles. Additional manufacturers have hired Greene to determine the cause and origin of fires in boats, buses and other large commercial vehicles. Moreover, Greene has investigated a number of fires caused by the deactivation switch in Ford vehicles, including reviewing the relevant scientific literature,” Kittredge wrote.

Ford Motor Co. argued that 5 Star offered no direct evidence that Ford admitted its design for the activation switch was negligent.

“To require an admission of a design defect by a manufacturer as a prerequisite for a negligence claim is not only contrary to law, but also is at odds with the policy of encouraging manufacturers to design products safely based on well-understood principles of safety and science,” Kittredge wrote. “The design defect involving the deactivation switch is grounded in basic science, which, according to Ford’s expert, is known to high school science students and, we think, should have been known to Ford engineers. A manufacturer may to avoid negligence liability by turning a blind-eye to the obvious.”

Amaris Elliott-Engel contributes to law.com.