As described in the last Criminal Justice column for the Santa Barbara Lawyer magazine, the California Supreme Court’s opinion in Sargon Enterprises v. University of Southern California, 55 Cal. 4th 747, 149 Cal. Rptr. 3d 614 (2012) made it clear that California is now, (and perhaps unsuspectingly has been for some time), a Daubert jurisdiction. This requires the trial court be the “gatekeeper” and make a determination as to the admissibility of scientific or expert testimony and to determine the limits of any testimony, if it is introduced. The Court held that there are essentially three criteria: The first criterion (1) is the matter on which an expert may rely; the second (2) is the reasons supported by the materials upon which the expert may rely; and the third (3) is the fact that the expert’s opinion may not be based on speculation.

As indicated in last month’s column, those criteria are not only consistent with the four part test proposed in articles published here several months before Sargon, but that the four part test is really required by both Sargon and Daubert. We ended Part I of this column by asking where do we go from here? We can agree, in general, that the Court in Sargon is saying that the trial judge is the gatekeeper and expects her or him to regulate what goes through the gate. The Court makes the valid point that, “The trial court’s gatekeeping role does not involve choosing between competing expert opinions.”

Therefore, going forward, there needs to be a rule that makes sense and is easy to apply. The four part rule, previously suggested remains as a valid application of the opinion in Sargon as well as the jurisprudence following Daubert. That is what we will explore in more detail in this Part II.