As a parent, sometimes the best (or only) answer you have for your kids is “Because I said so.” Fortunately as defense counsel in products liability cases, the law requires that plaintiff’s experts actually have some basis for his or her opinion. Ipse dixit should not be enough. Good news out of the state of Virginia. Recently, the state Supreme Court overturned a large jury verdict that was based on improper (“ipse dixit”) expert testimony. Hyundai Motor Company, Ltd. v. Duncan, 766 S.E.2d 893 (Va. 2015).

The case involved tragic facts which often can lead to tragic verdicts. The plaintiff sustained a serious head injury while driving a 2008 Hyundai when he lost control of the car and ultimately hit a tree on the driver’s side. Although the car was equipped with a side airbag, it did not deploy, and he sued Hyundai for breach of the implied warranty of merchantability on grounds the car was unreasonably dangerous. The plaintiff called an expert mechanical engineer who was permitted to testify that the side airbag should have been placed in a different location where it would have deployed and prevented the injury. The jury was apparently impressed by the testimony and returned a $14 million verdict.

The Virginia Supreme Court reversed and entered judgment for Hyundai. The Court carefully scrutinized the expert’s testimony and concluded it amounted to little more than “Because I said so.”

At trial, the expert’s principal conclusion was that Hyundai should have placed the sensor for the side airbag on the pillar on the driver’s side door and approximately 4 to 6 inches from the floor, which he believed would have resulted in the deployment of the airbag. In contrast, the sensor had actually been placed underneath the driver’s seat.

Interestingly, the expert conceded that Hyundai would have complied with the law had it not even had a side airbag, but opined that once you advertise you have one, it ought to work as intended. Point taken, perhaps.

In any event, the fundamental problem with this expert’s testimony is that he never tested his hypothesis that the sensor would have worked had it been moved to his chosen location. In fact, he relied on Hyundai’s own engineering study where it had analyzed 14 potential locations for the sensor – but Hyundai did not test the location he chose. The closest it came was to one spot on the pillar on the driver’s side door but that was 10-12 inches from the floor, not the 4 to 6 he believed would have saved the plaintiff. The expert chose the pillar as the appropriate spot because Hyundai’s own study showed that the sensor on the pillar at the spot 10-12 inches above the floor had a much a “better signal” than the spot Hyundai ultimately selected. On the back of essentially only that finding, the expert was permitted to testify that his chosen location would have prevented the injury.

However, on cross-examination the expert admitted “that the crash sensing system depends upon a combination of the structure of the vehicle, the sensors themselves, and an algorithm, but he did not perform any tests to determine whether a different sensor location, structure, or algorithm would have caused the side airbag to deploy in [plaintiff’s] crash.” In other words, there is simply more to the analysis that where the signal is strongest. The expert admitted all of those factors matter, but yet he ignored nearly all of them.

Presumably, Hyundai chose its location based on an analysis of all of the relevant factors. The opinion is silent as to why Hyundai chose the location it did and also why the expert did not simply choose a location that Hyundai tested as the more appropriate one. One can only guess that Hyundai’s study showed its chosen location was the best one and the expert could not challenge the study’s finding. So, instead, he hypothesized that a yet untested location was actually the best one of all.

As a result, the Virginia Supreme Court concluded that the expert’s conclusions were not reliable. The court was impressed that he admitted that “I have not done any tests . . . nor have I done any serious calculations. What I’ve done is look at the signal at the []pillar and the signal at the location and concluded that I got a much more robust and timely signal at the []pillar.” And he further admitted that the smallest difference in location (even less than an inch) could be critical, but, he selected a location that was more than 4 inches away from any location that had ever been tested before. He did not have a testable theory. He had only his own untested hypothesis.

That should not be enough under any standard, whether Daubert or otherwise. And the Virginia State Supreme Court held that the expert’s “opinion that the vehicle was unreasonably dangerous was based on his ipse dixit assumption that the side airbag would have deployed in [plaintiff’s] crash if the sensor had been located on the [] pillar. But the ‘analytical gap’ between the data [the expert] relied upon from Hyundia’s location study and the opinion he proffered was ‘simply too great.’” (internal citations omitted).

“Because I said so” can win a debate with your kids but it cannot prevent a $14 million verdict from being overturned in Virginia.