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Whom to Believe?


Whom to Believe?

September 13, 2019
Lisa P. Gruen

This article originally appeared in Goldberg Segalla’s Product Liability Playbook. Read the issue here.

Which expert witnesses measure up?

For years, there have been two standards of admissibility—the relatively lenient Frye, established in the 1923 case of Frye v. United States, and the more stringent Daubert, from 1993’s Daubert v. Merrell Dow Pharmaceuticals.

The Frye standard, which has been criticized as too vague and prone to “junk science,” says that for an expert’s opinion to be admissible it must be based on science “generally accepted” in the scientific community. Daubert requires more. According to that standard, the science behind an expert witness’s testimony must be not only generally accepted; it must also be testable and peer-reviewed and have a known potential error rate.

Until last year, all federal courts and 36 states followed the Daubert standard. But now, in two separate rulings since 2018, New Jersey and Florida have aligned themselves with Daubert. That’s good news for attorneys defending cases in those states—especially product liability cases—because plaintiffs will have to meet a higher standard before espousing scientifically unsupported expert opinions.

Here’s a look at what happened in the two states that just joined the ranks of Daubert believers:

New Jersey

On August 1, 2018, the New Jersey Supreme Court issued a landmark ruling in the case of In re Accutane Litigation, in which it essentially adopted the key factors set forth in Daubert as guideposts for determining the reliability of scientific expert evidence.

Accutane was a prescription medication developed by Roche that was effective in treating severe acne. In the case before the New Jersey Supreme Court, 2,000 plaintiffs alleged they developed Crohn’s disease because they took Accutane and the drug’s developer, Roche, filed a motion seeking a hearing on the association between Accutane and Crohn’s disease. At issue was the admissibility of scientific evidence under the New Jersey Rules of Evidence.

The Supreme Court discerned little distinction between “Daubert’s” principles regarding expert testimony and New Jersey’s, and Daubert’s factors for assessing the reliability of expert testimony “will aid New Jersey trial courts in their role as the gatekeeper of scientific expert testimony in civil cases.” The court reconciled the state with the federal Daubert standard to incorporate its factors for civil cases.

The non-exhaustive list of factors set forth in Daubert when assessing the validity and reliability of scientific expert testimony is now recognized in New Jersey. Despite adopting these factors, New Jersey had not previously and still has not formally adopted Daubert as its standard with regard to expert testimony.

The court noted, in its holding in Accutane, that both New Jersey law and the Daubert standard “are aligned in their general approach to a methodology-based test for reliability.” Both standards examine “whether an expert’s reasoning or methodology underlying the testimony is scientifically valid,” and “… whether that reasoning or methodology properly can be applied to [the] facts in issue.”

Given these similarities, the New Jersey Supreme Court was “persuaded that the factors identified originally in Daubert should be incorporated for use by [New Jersey] courts.” The court also clarified that “[d]ifficult as it may be, the gatekeeping role must be rigorous” and explained that while “the trial court should not substitute its judgment for that of the relevant scientific community,” the court’s proper “function is to distinguish scientifically sound reasoning from that of the self-validating expert, who uses scientific terminology to present unsubstantiated personal beliefs.” This means that, before permitting expert causation testimony to reach a jury, the court is required to conduct a “robust analysis of the methodology advanced” to determine whether the expert has “demonstrate[d] the validity of his or her reasoning.” Where a trial court determines that an expert has “applied a contradictory and selective form of reasoning” to reach his or her conclusions, those conclusions “should not be allowed to be advanced before a jury.”

Although it decried the Frye standard as being “unsatisfactorily constricting,” the New Jersey Supreme Court had ruled previously that it was possible that evidence could be put forward which was based on a causation theory that had not yet reached general acceptance in the scientific community but which could be found sufficiently reliable if based on a sound, adequately founded scientific methodology involving data and information of the type reasonably relied on by experts in the scientific field.

However, this relaxed or somewhat hybrid standard often resulted in uncertainty and in the court declining to do more than a superficial examination of whether the expert offered a plausible scientific explanation and whether the expert’s conclusions were based on the types of data and information reasonably relied on by comparable experts in the scientific field.

As such, the ruling in Accutane provided much-needed guidance to the trial courts as to their role in determining the admissibility of expert opinions. To date, there has been no negative treatment of this ruling in New Jersey.


On May 23, 2019, the Supreme Court of Florida, pursuant to its exclusive rulemaking authority granted by the Florida Constitution, adopted the Daubert standard as to the admittance of certain expert testimony into evidence. These Daubert amendments were codified into sections of the Florida Evidence Code.

These amendments were previously considered, applied (in 2013) and then rejected (in 2017-18), when the Florida Bar’s Code and Rules of Evidence Committee recommended that the Court decline to adopt the Daubert amendments to the extent that they were procedural in nature and risked violating the constitutional right to jury trial and access to the courts. In essence, the naysayers were concerned that, since the court acted as the gatekeeper over the admission of evidence in the form of expert testimony, it was abrogating a party’s right to a jury trial as the Court was weighing the evidence, not the jury. However, case law from a multitude of jurisdictions, including Texas and the Eighth Circuit, held that Daubert does not violate a party’s constitutional 7th Amendment right to a jury trial.

The Florida Supreme Court opined that the Daubert amendments remedied deficiencies caused by the Frye standard, which allowed an expert to testify based on his or her opinion, if such opinion was considered generally acceptable in the relevant scientific community. However, this often acted to allow into evidence expert opinions based on new or novel scientific techniques and/or opinions, which were not peer-reviewed or generally accepted in the scientific community, also known as “junk science.”

The Florida Supreme Court believed that Daubert “allowed the trial judge to ensure that any and all scientific testimony of evidence admitted is not only relevant but reliable.” (Daubert, at 589.) The Florida Supreme Court also felt that amending the Florida Evidence Code would create consistency between the state and federal courts with respect to the admissibility of expert testimony, which would promote fairness and predictability in the legal system, as well as help lessen forum shopping. The defense bar in Florida is reputedly quite pleased with the court’s action and, per the Florida Chamber of Commerce, this ruling “may help to end Florida’s reign as a judicial hellhole.”

A collaborative effort of Goldberg Segalla’s Product Liability practice group examining the latest practices, emerging developments, and influential court decisions in product liability law. View our most recent issue.