Daubert standard

The Daubert Standard is a legal precedent set in 1993 by the Supreme Court of the United States regarding the admissibility of expert witnesses' testimony during legal proceedings. The citation is Daubert v. Merrell Dow Pharmaceuticals, 509 U.S. 579 (1993).

A Daubert motion is a motion, raised before or during trial, to exclude the presentation of unqualified evidence to the jury. This is a special case of motion in limine, usually used to exclude the testimony of an expert witness who has no such expertise or used questionable methods to obtain the information.

Definition
In Daubert, the Supreme Court ordered federal trial judges to become the “gatekeepers” of scientific evidence. Trial judges now must evaluate proffered expert witnesses to determine whether their testimony is both “relevant” and “reliable”; a two-pronged test of admissibility.


 * The relevancy prong: The relevancy of a testimony refers to whether or not the expert’s evidence “fit” the facts of the case. For example, you may invite an astronomer to tell the jury if it was a full moon on the night of a crime. However, the astronomer would not be allowed to testify if the fact that the moon was full was not relevant to the issue at hand in the trial.


 * The reliability prong: The Supreme Court explained that in order for expert testimony to be considered reliable, the expert must have derived his or her conclusions from the scientific method. The Court offered "general observations" of whether proffered evidence was based on the scientific method, although the list was not intended to be used as an exacting checklist:
 * Empirical testing: the theory or technique must be falsifiable, refutable, and testable.
 * Subjected to peer review and publication.
 * Known or potential error rate.
 * Whether there are standards controlling the technique's operations.
 * Whether the theory and technique is generally accepted by a relevant scientific community.

Although trial judges have always had the authority to exclude inappropriate testimony, previous to Daubert, trial courts often preferred to let juries hear evidence proffered by both sides. Once certain evidence has been excluded by a Daubert motion because it fails to meet the relevancy and reliability standard, it will likely be challenged when introduced again in another trial. Even though a Daubert motion is not binding to other courts of law, if something was found not trustworthy, other judges may choose to follow that precedent.

History
Prior to Daubert, relevancy in combination with the Frye test were the dominant standards for determining the admissibility of scientific evidence in Federal courts. Frye is based on a 1923 Federal Court of appeals ruling (Frye v. United States 293 F. 1013 (DC Cir. 1923)) involving the admissibility of polygraph evidence. Under Frye, the Court based the admissibility of testimony regarding novel scientific evidence on whether it has "gained general acceptance in the particular field in which it belongs." The trial court's gatekeeper role in this respect is typically described as conservative, thus helping to keep pseudoscience out of the courtroom by deferring to those in the field.

In Daubert, the Supreme Court ruled that the 1923 Frye test was superseded by the 1975 Federal Rules of Evidence, specifically Rule 702 governing expert testimony. Rule 702 states, "If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise." In Daubert, the Court ruled that nothing in the Federal Rules of Evidence governing expert evidence "gives any indication that 'general acceptance' is a necessary precondition to the admissibility of scientific evidence. Moreover, such a rigid standard would be at odds with the Rules' liberal thrust and their general approach of relaxing the traditional barriers to 'opinion' testimony." However, some legal commentators argue that Daubert has resulted in a more conservative rather than liberal standard regarding the admissibility of expert evidence.

The Daubert standard was refined by two additional Supreme Court rulings; together known as the "Daubert trilogy." In Joiner (General Electric Co. v. Joiner, 522 US 136 (1997)), the Supreme Court held that an abuse of discretion standard of review was the proper standard for appellate courts to use in reviewing a trial court's decision of whether expert testimony should be admitted. Thus, appellate courts must defer to the lower trial courts decision regarding the admissibility of expert testimony unless they are strikingly wrong. In Kumho Tire, (Kumho Tire Co. v. Carmichael 526 U.S. 137 (1999)), the Supreme Court held that the judge’s gatekeeping function identified in Daubert applies to all expert testimony, including that which is non-scientific.

In 2000, the Supreme Court approved amendments to the Federal Rules of Evidence relating to opinion evidence and expert testimony to conform to the "Daubert trilogy." In addition to amending Rules 701 and 703, Rule 702 now includes the additional provisions which state that a witness may only testify if, "1) the testimony is based upon sufficient facts or data 2) the testimony is the product of reliable principles and methods, and 3) the witness has applied the principles and methods reliably to the facts of the case."

Story
In the Daubert case, Merrell Dow was sued by a mother whose baby had a congenital disorder. That mother had taken Bendectin, an anti-nausea drug made by Merrell Dow, during her pregnancy. Merrell Dow moved for summary judgment, claiming Bendectin had not caused the child's disorder. In the affidavit authored by Dr. Steven H. Lamm, the author testified that he had reviewed multiple published human studies and concluded the use of Bendectin during the first trimester of pregnancy was not supposed to be a health risk. In response to Merrell Dow's affidavit, the plaintiff presented eight affidavits solely based on animal testings, claiming the existence of a link between Bendectin and animal birth defects.

The court granted summary judgment for Merrell Dow and dismissed the case, finding Daubert's experts relied on evidence "not sufficiently established to have general acceptance in the field to which it belongs." The Court held that expert opinion which is not based on data from the field of epidemiology concerning Bendectin is not admissible to raise an issue regarding causation (in law) to the jury. In addition, the Court also ruled that although Daubert's experts recalculated data obtained from previously published epidemiologic studies, their findings were not considered admissible because they were neither published nor subjected to peer review. The plaintiffs appealed the decision, and, in due course, the case reached the U. S. Supreme Court

The Supreme Court did not apply their new Daubert standard to the case, but rather reversed the decision and remanded the case to the Ninth Circuit court. On remand, the Ninth Circuit applied the Daubert standard and again granted summary judgment for the defendant.

Commentary
The Daubert decision was heralded by many observers as one of the most important Supreme Court decisions of the last century imparting crucial legal reforms to reduce the volume of what has disparagingly been labeled junk science in the court room. Many of these individuals were convinced by Peter Huber’s 1991 book Galileo’s Revenge: Junk Science in the Courtroom which argued that numerous product liability and toxic tort verdicts were unjustly made on the basis of junk science. According to Huber, junk science in the courts threatened not only justice but the workings of the American economy. This threat rested on two premises: 1) juries are not competent to recognize flaws in scientific testimony, especially toxic tort or product liability suits where decisions on causation rested on complex scientific issues; and 2) the result of junk science is the issuance of awards that deter manufacturers from introducing worthwhile products into the marketplace out of fear of unwarranted tort liability for injuries their products have not caused. By requiring experts to provide relevant opinions grounded in reliable methodology, proponents of Daubert were satisfied that these standards would result in a fair and rational resolution of the scientific and technological issues which lie at the heart of product liability adjudication.

According to a 2002 RAND study, post Daubert, the percentage of expert testimony by scientists that was excluded from the courtroom significantly rose. This rise likely contributed to a doubling in successful motions for summary judgment in which 90% were against plaintiffs. Beyond this study, there is little empirical evidence of the impact of Daubert. However, some critics argue that Daubert has disrupted the balance between plaintiffs and defendants, “The exclusion of expert testimony affects plaintiffs far more than defendants because plaintiffs may then not be able to meet their required burden of proof. Furthermore, there is little point in plaintiffs going to the expense of Daubert motions to exclude defendant’s experts until they know if their case will proceed. So if more experts are now being excluded, then Daubert has undoubtedly shifted the balance between plaintiffs and defendants and made it more difficult for plaintiffs to litigate successfully.”

A different pattern has emerged in criminal cases. In criminal cases, the prosecution has the burden of proof and uses a host of forensic science methods as evidence to prove their case. But, Daubert motions are rarely made by criminal defendants and when they do, they lose a majority of the challenges.

Some commentators believe that Daubert caused judges to become--in the phrase used in former Chief Justice William Rehnquist’s dissent in Daubert--amateur scientists; many lacking the scientific literacy to effectively fulfill their role as gatekeeper of scientific evidence. Although “science for judges” forums have emerged in the wake of Daubert in order to educate judges in a variety of scientific fields, critics remain critical about the usefulness of the Daubert standard in discerning valid science.