Before the Court En Banc (Parraguirre and Pickering recused). Opinion by Hardesty.
In these consolidated writ petitions arising from actions involving the hepatitis C outbreak at the endoscopy clinic in Las Vegas, the Court considered: (1) procedurally, whether a writ is a proper vehicle for challenging an adverse evidentiary ruling regarding expert testimony; (2) whether a nurse is per se prohibited from offering an expert opinion regarding causation; and (3) what level of certainty is required for defense expert testimony regarding medical causation if it is offered to contradict the plaintiff’s theory and not as an independent opinion of causation. The Court determined that a writ petition challenging an evidentiary decision generally will not be considered; however, if the petition presents an issue of first impression and fundamental public importance, the Court may choose to consider it. The Court will be more likely to consider a writ petition from an evidentiary ruling if it also serves judicial economy, as in this case where there are multiple actions proceeding in the district courts and two courts had reached contradictory rulings. Addressing the substance of the case, the Court rejected the argument that because the statutory definition of a registered nurse excludes "acts of medical diagnosis" nurses should be prohibited from offering opinions as to medical causation. The Court reaffirmed its flexible, case-specific test for determining if an expert is qualified, holding that a nurse may be qualified to testify regarding causation if he or she has the requisite specialized skills, knowledge, experience or training. The major rule of the opinion reduces the level of certainty a defense medical expert needs to be able to contradict a plaintiff’s theory of causation. The Court reaffirmed that if a defense expert offers an independent theory of causation and does not include the plaintiff’s theory in his or her analysis at all, that opinion must be supported by a reasonable degree of medical probability. However, if a defense expert is offering an opinion of causation that simply calls the plaintiff’s theory into question by comparing it to other possible causes, the expert’s opinion need only be non-speculative, relevant, and supported by competent medical research. Writs of mandamus granted in part and denied in part. (Kerry Doyle, Associate in the Reno office of McDonald Carano Wilson)
