City of Pomona v. SQM

Using a methodology known as "stable isotope analysis," an expert hired by the city determined that the most likely dominant source of the perchlorate found in the city's groundwater was sodium nitrate that had been used as fertilizer. The city sued SQM, the company that imported sodium nitrate into the United States. Before trial, the district court held an evidentiary hearing under Daubert v. Merrell Dow Pharmaceuticals, Inc., and excluded the city's expert. The court reversed the district court's exclusion of the expert's testimony. The district court should not have made credibility determinations that were reserved for the jury; the Federal Rules of Evidence did not require an endorsement from the EPA approving the expert's results and the district court's conclusion to the contrary was an abuse of discretion; the district court erroneously ruled that the expert's methodologies have not been and cannot be tested; and the district court's resolution of the reference database was an abuse of discretion and sufficient grounds for reversal where the matter was for the jury to decide. The court affirmed the district court's denial of SQM's motion for summary judgment where SQM failed to show that there was no genuine factual dispute as to whether the city's claims were barred by the economic loss rule or by the applicable statute of limitations. View "City of Pomona v. SQM" on Justia Law