A Prolonged Battle of the Experts In Groundwater Contamination
City of Pomona v. SQM North America involves the contamination of groundwater with perchlorate which the city argues was sourced from fertilizer imported by SQM North America from the Atacama Desert. In 2011, City of Pomona's expert Neil Sturchio was excluded by the district court from testifying about the source of groundwater contamination. The Ninth Circuit ultimately reversed the exclusion and remanded for trial, stating that the faults found by the district court go to the weight of the testimony. After trial on remand in 2015 and a verdict for the defense, the City of Pomona has appealed again. This time, the main issues revolve around the admission of defendant's expert Dr. Richard Laton, a groundwater contamination expert.
JuriLytics first became interested in City of Pomona v. SQM North America late 2014 when SQM North America petitioned the Supreme Court to resolve an apparent split in the circuits regarding the application of Daubert after the Ninth Circuit's ruling. The petition was denied. On its own, JuriLytics commissioned independent peer review of Dr. Sturchio's expert opinions to understand how the scientific community views perchlorate analysis. Our neutral peer reviewers found, post-hoc, that the methods utilized by Dr. Sturchio were state-of-the-art and accepted by the geochemistry community (see the full case study here).
On its second appeal, the City of Pomona argues that there was further improper handling of expert testimony by the district court. First, the City argues that Dr. Sturchio, after three and one-half years, was not able to update his report on remand that addressed many of the issues that 1) the district court originally used as grounds to exclude him and 2) the defense experts found faulty. Second, the city argues that the district court improperly admitted Dr. Laton's opinions stating that there were many alternative sources (besides fertilizer) of perchlorate in Pomona's groundwater as being either irrelevant, unreliable, or both.
Amicus Analysis: Integrating Scientific Progress and Carefully Analyzing The Relevance of Expert Opinion
Prof. Faigman's amicus brief analyzes both issues, and concludes in the first issue that the district court did abuse its discretion in prohibiting Dr. Sturchio from updating his report with additional data. He argues that science is always progressing, and accurate and up-to-date data is necessary for a jury to fairly weigh the testimony. The other side of the balance is that discovery must end at some point for the law to resolve a dispute with some finality. In this case, the opinions of Dr. Sturchio would not have changed; he simply would have had more data to justify his conclusions. Narrow discovery could easily have been opened to allow the most up-to-date scientific information to inform the case.
With regard to Dr. Laton's expert opinions, Prof. Faigman argues that the opinions were improperly admitted because the district court did not provide any rationale for why Dr. Laton was qualified to testify even though a Daubert challenge had been raised. In addition, Prof. Faigman argues that had the district court performed the analysis, the court would have found his testimony to be irrelevant and/or unreliable. It is irrelevant because his alternative sources are those he claims that plaintiff's expert did not consider. This is contrary to Dr. Sturchio's opinions, which explicitly considered many of the sources Dr. Laton describes. Second, even in the cases where plaintiff's experts did not explicitly consider the sources mentioned by Dr. Laton, he provides no basis or analysis to indicate why they might have been neglected. For both reasons, Prof. Faigman argues that Dr. Laton's opinions on alternative sources of perchlorate should have been excluded.
The Views of Mainstream Science
Prof. Faigman's analysis is confirmed by a second set of JuriLytics' peer review. This second set of peer review utilized two reviewers, Drs. Chamberlain and Hernes, of Stanford and UC Davis, respectively. The peer reviewers were given the reports of four experts, Drs. Sturchio, Wheatcraft, Aravena, and Laton. Drs. Wheatcraft and Laton are groundwater contamination experts, while Drs. Sturchio and Aravena are isotope geochemistry experts. In reviewing the four reports, the peer reviewers found that the methods of Dr. Sturchio were top-notch. At the same time, the reviewers questioned many of Dr. Laton's criticisms, stating that many of the sources he alleges were not considered were in fact considered by Dr. Sturchio. Ultimately, the peer review represents a central tenet of Daubert: is the testimony of the expert generally accepted? For Dr. Sturchio, the answer is essentially yes. For Dr. Laton, the answer is essentially that his opinions were irrelevant.
City of Pomona v. SQM North America illustrates the problems that litigators are all to familiar with when it comes to expert testimony. Good science doesn't always mean victory. The challenges lie not in having science on your side, they lie in convincing courts that the science you are presenting is valid. This process of convincing courts is not straightforward in the adversarial system. Arguments come in pairs. When science is introduced, judges often have difficulty deciphering which argument represents mainstream science. Of course, courts do the best they can, but often the responsibilities bestowed upon them are greater than even researchers have in evaluating complex science. If psychologists don't evaluate (peer review) medical causation, why do we expect judges to evaluate fields from acoustics to zoology? Independent peer review, in this case, confirms what close inspection of the expert reports reveal. It stands to reason that this close inspection is often taxing. Courts should have help. They should have peer review.