Fake Cop “Experts”: Yes, Daubert Applies to Them Too – Sort of Sort of.

May 16, 2017
By Hanging Out with Carl Gunn


  • The Ninth Circuit has held a court isn’t absolutely required to hold a pretrial hearing in order to perform its gatekeeping role under Daubert.
  • Still, the court has recognized such a hearing is appropriate in certain cases and acknowledged the difficulties of requiring an attorney to explore the Daubert issues in front of the jury.
  • The final decision usually lies in the discretion of the trial court, so you can argue for a pretrial hearing even if one isn’t absolutely required.



In my last post, I talked about the case law holding that Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), applies to cop “experts” just like it applies to scientific experts, but not necessarily with the same particular “Daubert factors.”  Rather, courts can be flexible and have discretion about what factors they look to in performing their Daubert “gatekeeping role” of determining the reliability of proffered expert testimony.  They can use the factors listed in Daubert if they think them appropriate, but don’t need to use those factors if they consider them inapplicable.

Another way in which we wanted to read Daubert when it first came out is to mandate a pretrial evidentiary hearing at which we’d get to question the purported “expert” outside the presence of the jury.  The Ninth Circuit considered this in the case of a cop “expert” in United States v. Alatorre, 222 F.3d 1098 (9th Cir. 2000), and I’m afraid it didn’t give us what we wanted there either.  The court held the district court is not required to hold a separate, pretrial hearing outside the presence of the jury.  See id. at 1100.  The court acknowledged Daubert does impose a “gatekeeping” duty on the district court “requiring the court to screen[ ]” the proffered evidence to “ensure that any and all [expert] testimony or evidence admitted is not only relevant, but reliable.”  Alatorre, 222 F.3d at 1100-01 (quoting Daubert, 509 U.S. at 589).  But the court opined that “[n]owhere in Daubert, [General Elec. Co. v.] Joiner[, 522 U.S. 136 (1997)], or Kumho Tire[ Co. v. Carmichael, 526 U.S. 137 (1999),] does the Supreme Court mandate the form that the inquiry into relevance and reliability must take.”  Alatorre, 222 F.3d at 1102.  The court then noted Kumho Tire’s statement that district courts have “broad latitude,” Alatorre, 222 F.3d at 1102 (quoting Kumho Tire, 526 U.S. at 153), and held this meant a pretrial hearing outside the presence of the jury is not required, see id. at 1100, 1102.

The good news is that Alatorre by no means held a court cannot hold a pretrial hearing outside the presence of the jury.  To the contrary, Alatorre recognized that holding such a hearing “may be appropriate in certain cases.”  Id. at 1105.  It also affirmatively cautioned that “[t]rial courts should be mindful of the difficulties posed when counsel must explore an expert’s qualifications and the basis for the expert’s opinion in the presence of the jury and, depending on the circumstances of the case, should give due consideration to requests that questioning occur unconstrained by that presence.”  Id.  Alatorre simply held that “in the end, such a determination is a judgment call best left to the discretion of the trial court.”  Id.

This reference to discretion and the court’s quotation of Kumho Tire’s recognition of “broad latitude” in the district court bring us back to the point that I made at the end of the last post.  All Alatorre and these other cases generally hold is that the district court didn’t abuse its broad discretion by acting as it did.  That means in most instances the court could just as easily have gone the other way.  So remind the court of that if and when the holding of Alatorre gets thrown in your face, and point at the same time to the caveats noted in the preceding paragraph.