Kumho is important to litigation practitioners because it clarified the role of the trial court in making its preliminary determination regarding the relevance and reliability of expert testimony. In Kumho, the Supreme Court held that the Daubert factors may apply to the testimony of engineers and other experts who are not scientists (e.g., valuation analysts and economists), and instead rely upon "technical" or other "specialized" knowledge. The case established that nonscientific opinions on financial or accounting issues are subject to the Daubert expert testimony guidelines.
In this product liability case, Patrick Carmichael was driving his minivan when one of the tires—manufactured by Kumho Tire Company—blew out, causing the vehicle to overturn, killing one passenger and injuring others. The survivors and the representatives of the decedent's estate sued Kumho, claiming that the tire was defective. Dennis Carlson, Jr., an expert in tire failure analysis, in essence, opined that a defect in the tire's manufacture caused the blowout, based upon his inspection of the tire and his theory that "in the absence of at least two specific, physical symptoms indicating tire abuse, the tire failure of the sort that occurred here was caused by a defect."
Kumho moved to exclude the testimony of the tire failure expert on the ground that his methodology failed to meet the requirements of Federal Rule of Evidence 702. The District Court—acting as a reliability "gatekeeper" under Daubert — ruled that the expert's methodology did not satisfy any of the four Daubert factors used to determine the reliability of the expert's scientific theory or technique.
The plaintiffs appealed and the U.S. Court of Appeals for the Eleventh Circuit ruled that the District Court erred in its application of Daubert. The Eleventh Circuit reasoned that Daubert was limited to scientific evidence, and that the Daubert factors did not apply to the tire failure expert's testimony. The Supreme Court reversed the Eleventh Circuit and affirmed the trial court's decision to exclude the expert's testimony.
The Supreme Court decided that the application of the Daubert reliability factors showed Carlson's methodology to be unreliable. The plaintiffs could not establish that Carlson's methodology could reliably determine the cause of the tire's failure: (1) other experts in the industry did not essentially use Carlson's methodology; and (2) Carlson's approach was not validated in publications.
The Supreme Court viewed the trial court as a "gatekeeper" regarding the reliability of expert testimony, "whether the specific expert testimony focuses upon specialized observations, the specialized translation of those observations into theory, a specialized theory itself, or the application of such a theory in a particular case."