US v. Bacon, No. 18-50120 (11-5-20) (En Banc). What does the 9^th do when a trial court commits Daubert error? What is the remedy? The precedent for trial court errors, such as incorrect legal standards, was a bright-line new trial if non-harmless. This was to enforce FRE 702 and the gatekeeper functions. However, if the record is incomplete, should a panel be allowed to remand to see if the evidence could be admitted or precluded on other grounds? The 9^th concludes that an inflexible binary remedy is not appropriate. Each case – and possible error – may differ with the circumstances. The 9^th holds that when there is a “non-harmless Daubert error, the panel has discretion to impose a remedy ‘as may be just under the circumstances’.” (10). The 9^th may require a new trial sometimes; a limited remand in others. Daubert errors are remedied not by a special category, but under the usual appellate rules.

Prior caselaw that conflicts with this holding (requiring a remand) are overruled: Mukhar, Barabin II, and Christian.

The decision is here:

https://cdn.ca9.uscourts.gov/datastore/opinions/2020/11/05/18-50120.pdf