Legal ·
Daubert and Frye are the two framework families that govern expert testimony in U.S. courts: Daubert asks whether a method is reliable and reliably applied, and Frye asks whether it is generally accepted in the field. Neither framework routinely excludes forensic economic testimony; challenges target inputs the record does not support.
Daubert and Frye are the names attorneys use for the two families of expert admissibility framework in U.S. courts. Under Daubert, which federal courts and most state courts follow, the trial judge decides whether an expert's method is reliable and reliably applied to the facts of the case. Under Frye, which a smaller number of states retain, the question is whether the method is generally accepted in the relevant professional community. Which framework applies shapes how an economic damages report is written, how the economist is prepared for deposition, and how an opposing report is challenged. Attorneys are responsible for confirming the governing framework against primary sources.
The two families are not two settings of the same rule. The Daubert framework lists several factors and treats general acceptance as one of them; the Frye framework asks the general-acceptance question alone. Federal courts apply Daubert, most states apply it or a close variant, and the remaining states apply Frye or a hybrid. The federal versus state court guide lists the questions to ask about a venue before the report is finalized.
Under the Daubert framework, the trial judge acts as a gatekeeper with an affirmative obligation to ensure that expert testimony meets threshold requirements of reliability and relevance before the jury hears it. The non-exclusive factors include whether the method has been tested, whether it has been subjected to peer review and publication, its known or potential rate of error, the existence and maintenance of controlling standards, and whether the method is generally accepted in the relevant professional community. General acceptance is one factor among several rather than the sole criterion, and the inquiry applies to technical and other specialized knowledge, including economics, not only to laboratory science.
The Frye framework asks a narrower question: whether the expert's method is generally accepted in the relevant community. Courts applying it do not separately evaluate testability, peer review, or error rates. The framework is sometimes described as more conservative toward novel methods and more permissive toward established ones, and for forensic economics the practical difference is small, because the discipline's core methods are established under either test.
What those methods are matters for the analysis. Projection of earnings from documented history with published wage growth, worklife expectancy from published tables, replacement cost valuation of household services from time-use and occupational wage data, personal consumption deductions from household expenditure data, and discounting at low-risk yields are taught in the field's literature, published in its journals, and applied by economists on both sides of the bar. Challenges to economic testimony therefore seldom argue that the discipline is unreliable. They argue that the economist's inputs are unsupported by the record or that the method was not reliably applied to the facts.
The recurring grounds are familiar. An earnings base that departs from the tax returns without explanation. A growth rate drawn from one period and a discount rate from another. A worklife horizon that assumes work to an age no table supports, or a retirement age with no basis in the record. Post-event earnings that ignore a documented return to work, or that adopt a capacity opinion no vocational or medical evidence supports. A death claim without a personal consumption deduction. A lost profits projection for a business with no operating history and no comparable. Courts have held that an opinion connected to the data only by the expert's assertion may be excluded, and each of these gaps is an example.
The defense to those challenges is the report itself. A report that states every input, identifies its source, uses published series and tables the other side can check, shows the sensitivity of the result to the contested assumptions, and stays within the economist's field is positioned to be examined on the merits rather than excluded at the threshold. The expert witness testimony guide describes how the report, the deposition, and the trial presentation fit together, and the rebuttal guide describes how the same gaps are found in an opposing report.
Practitioners should be aware that several states apply modified or hybrid versions of these frameworks, and some have codified their admissibility rules in evidence statutes. Counsel preparing for expert litigation in an unfamiliar jurisdiction should research the applicable framework against primary sources and the case law applying it to economic testimony in particular.
Request a consultation on Legal or call (201) 343-0700. Plaintiff and defense counsel.