Daubert Standard

Daubert v. Merrell Dow Pharmaceuticals is the leading United States Supreme Court case on the admissibility of expert witness's opinion as evidence in federal courts in the United States. It overruled the previous test outlined in Frye v. United States , which required such evidence to be generally accepted in the scientific community.

Daubert Standard

The test in Daubert was later extended to merely technical evidence in Kumho Tire v. Carmichael . Although the decision in Daubert was only binding on federal courts, many state courts now also use the Daubert test when determining whether expert opinion testimony is admissible. In its essence, Daubert expanded the type of scientific evidence that could be admitted in federal courts. However, it also allowed judges to make a determination of the admissibility of such evidence in a viva voce hearing prior to the evidence being introduced to a jury, rather than just allowing the court to speak as to the weight that should be given to that evidence.

The Case

The plaintiffs in Daubert were parents of children born with birth defects. The theory of their case was that those defects were caused by the defendant's drug Benedictin . The matter proceeded to summary trial before a judge, who heard expert evidence from well qualified scientists on both sides. The defendant's expert testified that the scientific community was generally of the opinion that Benedictin could not have caused the defects the plaintiffs' children had suffered. However, the plaintiff's experts noted certain data in existing chemical and animal studies that could be interpreted to show that the drug could have been responsible for the defects seen. Given the rule in Frye, the court ruled that as only the defendant's theory was generally accepted, the plaintiff's expert testimony could not be admitted despite the soundness of the science behind it. As such, the trial judge ruled summarily for the defendants and dismissed the case. The plaintiffs appealed and the appeal reached the Supreme Court.

The Supreme Court Decision

The court, in a unanimous decision, reversed the trial judge and remanded the case to the original court for a re-hearing. The court noted that Rule 702 of the Federal Rules had been passed since the Frye case was decided in 1923. That rule stated:

"If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to 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."

As such, the court outlined what considerations the evidence had to be given to be admissible, ruling that the "generally accepted" rule was too restrictive. The considerations outlined by the court were:

• Whether the theories and techniques employed by the scientific expert have been tested. This only required that the theories had been subject to experimental test and not been falsified. It did not require proof that the theory or technique had been proven.
• Whether they have been subjected to peer review and publication. As such, there was no requirement that the theory been accepted by the scientific community, only that it had been reviewed by people in the field. However, theories that had not been reviewed or published could be excluded.
• Whether the techniques employed by the expert have a known error rate . This would require an indication that the science behind the theory had been tested and the limitations of the technique could be assessed by the trier of fact.
• Whether the theories are subject to standards governing their application, such as a group of scientists doing similar work employing the same standards.
• Whether the theories and techniques employed by the expert enjoy widespread acceptance. In other words, they do not need majority support of the scientific community, only a substantial minority need support the work.

Aftermath

After Daubert, it was expected that the range of scientific opinion evidence used in court would be expanded. However, courts have strictly applied the standards in Daubert, and it has generally been successful in excluding "junk science" or "pseudoscience", as well as techniques that are merely experimental.

It should be noted that the considerations in Daubert do not all have to be met for the evidence to be admitted. It is only necessary that the majority of the tests be substantially complied with.

The principle in Daubert was expanded in Kumho Tire, where the evidence in question was from a technician and not a scientist. The technician was going to testify that the only possible cause of a tire blowout must have been a manufacturing defect, as he could not determine any other possible cause. The Court of Appeal had admitted the evidence on the assumption that Daubert did not apply to technical evidence, only scientific evidence. The Supreme Court reversed, saying that the standard in Daubert could apply to merely technical evidence, and that in this case the evidence of the proposed expert was not sufficiently reliable.

External Links

• The case at Findlaw.com
• Daubert on the Web