On May 16, 2022, the Supreme Court declined to review an Eighth Circuit decision that drastically lowered the bar for admitting unreliable expert evidence in federal court. The decision was a setback for WLF, which joined Atlantic Legal Foundation and  DRI—The Voice of the Defense Bar in urging the Court to grant review. The case arose from long-running multi-district litigation over 3M Company’s Bair-Hugger patient warming system, which remains the most popular choice of surgeons for ensuring patient comfort and safety during surgery. Citing grievous flaws, weaknesses, and gaps in the Plaintiffs’ experts’ causation testimony, the district court excluded their reports as unreliable. But the Eighth Circuit reversed, holding that expert testimony must be admitted unless it is “so fundamentally unsupported by its factual basis that it can offer no assistance to the jury.” As WLF’s brief explained, that is not the standard for reliability established by either Federal Rule of Evidence 702 or applicable Supreme Court precedent. WLF’s brief argued that the Eighth’s Circuit lax standard for admitting expert evidence places a heavy thumb on the side of admitting expert evidence with acknowledged flaws and deprives defendants of a fair trial and due process.


Amicus brief