Daubert and Robinson Standards

The Daubert and Robinson standards together establish the Texas framework for judicial gatekeeping of expert witness reliability. The Texas Supreme Court adopted the federal Daubert framework in E.I. du Pont de Nemours & Co. v. Robinson, 923 S.W.2d 549 (Tex. 1995), and elaborated it through six non-exclusive factors evaluating the reliability of scientific expert testimony. Gammill v. Jack Williams Chevrolet, Inc., 972 S.W.2d 713 (Tex. 1998), extended reliability gatekeeping to all expert testimony, including non-scientific or experience-based opinion, through the "analytical gap" test.

The six Robinson factors

Rule 702 of the Texas Rules of Evidence permits expert testimony only where it will assist the trier of fact and the witness is qualified. Robinson articulates six non-exclusive factors for evaluating the reliability of scientific expert testimony: (1) the extent to which the underlying theory has been or can be tested; (2) the extent to which the technique relies on the subjective interpretation of the expert; (3) whether the theory has been subjected to peer review and publication; (4) the technique's potential rate of error; (5) whether the underlying theory or technique has been generally accepted as valid by the relevant scientific community; and (6) the non-judicial uses to which the technique has been put. No single factor is dispositive; the trial court applies them flexibly.

Gammill and the analytical gap test

Gammill v. Jack Williams Chevrolet, Inc., 972 S.W.2d 713 (Tex. 1998), extended Robinson's reliability gatekeeping to non-scientific expert testimony, experience-based opinion in fields like accident reconstruction, business valuation, and various engineering disciplines. Where the Robinson factors don't fit (because the testimony isn't subject to scientific testing in the traditional sense), the trial court must still determine reliability, and Gammill adopted the question posed in Joiner: whether there is simply too great an analytical gap between the data and the opinion proffered. The analytical gap is the disconnect between the data and the conclusion, courts exclude opinions where the gap is too wide.

Procedural mechanics, the Daubert challenge

Reliability challenges to expert testimony are typically raised pretrial through motion to exclude (sometimes called a "Daubert motion" or "Robinson motion"). A typical sequence: (1) timely written objection identifying the specific reliability concerns; (2) motion to exclude with supporting evidence; (3) hearing, the trial court has discretion whether to conduct an evidentiary hearing; (4) a ruling on admission or exclusion. To preserve a reliability complaint, a party must object before trial or when the evidence is offered. Unless the court orders otherwise, Tex. R. Civ. P. 195.2 requires a party seeking affirmative relief to designate experts 90 days before the end of the discovery period, and other parties 60 days before.

Soft sciences and experience-based testimony

For "soft sciences", psychology, psychiatry, social sciences, and pure experience-based opinion, courts often use the framework from Nenno v. State, 970 S.W.2d 549 (Tex. Crim. App. 1998), overruled on other grounds by State v. Terrazas, 4 S.W.3d 720 (Tex. Crim. App. 1999), rather than the Robinson factors. The court evaluates whether the expert's field is legitimate, whether the testimony falls within that field, and whether the expert is properly applying the field's methods to the facts. Experience alone may provide a sufficient basis for expert testimony in some cases but not in every case, and the trial court, as gatekeeper, decides whether it does. Bare credentials plus conclusion is not enough; the expert must show some methodology connecting facts to conclusion.

Common reliability problems

Recurring patterns of expert exclusion: (1) untested methodology, opinions based on novel theories without empirical validation; (2) excessive subjectivity, opinions that rely entirely on the expert's intuition without disclosed methodology; (3) analytical gap, conclusions that don't follow from the disclosed data; (4) application to facts, methodology that may be reliable in general but is not properly applied to the case facts; (5) scope, opinions outside the expert's qualifications; (6) ipse dixit opinions, "because I said so" without disclosed reasoning.

Full entry: Daubert and Robinson Standards