Acosta v. Shell Western Exploration and Production, Inc.

Summary

The New Mexico Supreme Court held that the district court applied an incorrect standard when excluding expert and scientific evidence offered to establish that petrochemical exposure caused autoimmune disorders. The court concluded that the epidemiological study, animal studies, and related expert testimony were probative of causation and should have been admitted, even if they were not independently sufficient to establish the plaintiffs' entire burden of proof. It reversed the partial summary judgment for Shell and remanded for further proceedings.

Holdings

1. Expert evidence is admissible under Rule 11-702 when the expert is qualified, the testimony assists the trier of fact, and the testimony concerns scientific, technical, or specialized knowledge with a reliable basis. Relevance is a minimal threshold; evidence need only have a tendency to make a fact more or less probable.
2. New Mexico does not adopt the Joiner rule permitting a judge to reject expert testimony merely because the analytical gap between the underlying evidence and the expert's conclusion is too great.
3. A toxic-tort plaintiff must establish general causation—that the suspected agent is capable of causing the injury in the general population—and specific causation—that the agent actually caused the plaintiff's injury. Evidence need not conclusively establish general causation to be admissible if it is scientifically valid and probative of causation.
4. Partial summary judgment for Shell on the lupus and autoimmune-disorder claims was improper because it resulted from the erroneous exclusion of plaintiffs' general-causation evidence, which created a genuine issue of material fact.

Questions Presented

1. Whether the district court applied an incorrect standard when it excluded Dr. Dahlgren's epidemiological study, animal studies, and causation testimony as irrelevant or insufficient to establish general causation.
2. Whether New Mexico law permits exclusion of expert testimony because of an allegedly excessive analytical gap between the underlying data and the expert's conclusions.
3. Whether partial summary judgment was proper after exclusion of the plaintiffs' general-causation evidence.

Disposition

reversed_and_remanded