Expert witness testimony is often crucial to a solid legal case. This is especially true when the plaintiff or defendant needs to present sophisticated concepts to the jury. Good expert testimony can sway the jury’s opinion. Bad testimony can taint it.
Accordingly, it is important that your legal team should challenge unreliable witness testimony. There are two key standards for the admission or exclusion of expert witnesses – the Daubert standard and the Frye standard. Often, the exclusion of a plaintiff’s expert witness will leave them without a proper case, and the court must enter summary judgment against them. When that exclusion follows the Daubert standard, you can call it a “Daubert win.”
Daubert versus Frye
The Daubert and Frye standards are both named after the cases that shaped them:
- The Frye standard took shape in a D.C. Circuit case, Frye v. United States
- The Daubert standard originated with a Supreme Court decision in Daubert v. Merrell Down Pharmaceuticals, Inc.
Notably, the Daubert standard is newer than the Frye standard. Frye took place in 1923. The Daubert standard followed 70 years later in 1993. In most cases, you would expect a newer decision by the U.S. Supreme Court to completely overshadow an older circuit court decision, but some states, such as Illinois, still adhere to the Frye standard.
As the older standard, Frye is slightly less demanding. It requires that expert witnesses who want to use a “scientific principle or discovery” in their testimony must be able to show that principle has received general acceptance within the scientific community. In the words of the D.C. Supreme Court, “[T]he evidential force of the principle must be recognized.” It doesn’t matter if the data are wrong. If the witness is an “expert” and a sizeable portion of the scientific community has validated the principle, the testimony is allowed.
The main difference between the standards, then, is that the Daubert standard invites the judge to act as a “gatekeeper” to allow all good testimony and bar the bad. The U.S. Supreme Court does not mean for judges to act as scientific experts, but to consider several factors relating to the witness’s qualifications and the reliability and relevance of the testimony.
A closer look at the Daubert standard
When determining the witness’s qualifications under the Daubert standard, judges should consider one or more of five listed factors:
Likewise, the Supreme Court instructs judges using the Daubert standard to consider five factors related to the reliability of witness testimony:
- Whether the theory or technique in question can be (and has been) tested
- Whether it has been subjected to peer review and publication
- Its known or potential error rate
- The existence and maintenance of standards controlling its operation
- Whether it has attracted widespread acceptance within a relevant scientific community
Finally, the Daubert standard asks judges to consider the relevance of the testimony. It’s one thing for the testimony to adhere to accepted practices and have strong scientific foundations; it’s another question entirely whether the testimony has any connection to the facts of the case. In addition, relevant testimony should meet three additional tests:
- It should clarify issues that the average layperson may not understand without help
- It should not interfere with the duties of the judge by instructing the jury about the laws in question
- It should not interfere with the duties of the jury by applying the law to the facts in question
As you can see, the Daubert standard offers judges more leeway to determine the appropriateness of expert testimony. They have a wide range of factors to consider, and it is important to challenge significant weaknesses in any of an opponent’s witnesses’ qualifications, reliability or relevance.
Daubert wins are big
We mentioned it earlier, but it is worth repeating: Winning a Daubert motion to exclude an opponent’s witness can break a case wide open. This is true regardless of the type of case. Expert testimony can play a role in anything from construction law and insurance defense to personal injury and criminal defense.
It is also notable that Daubert motions tend to come prior to trial. That means that winning them, and winning the summary judgement that often follows, can save you a lot of time and money. Winning a case in trial is good. Winning your case before you get to trial is even better.