By Lee Mickus, a Partner in the Denver, CO office of Evans Fears Schuttert McNulty Mickus LLP. Mr. Mickus is also Co-Chair of the Rule 702 committee for Lawyers for Civil Justice.


Prior to the Rule 702 amendments that took effect on December 1, 2023, three misconceptions of the Rule 702 standard appeared frequently in rulings addressing the admissibility of opinion testimony.  First, despite the explicit directives of Rule 702(b) and (d), many decisions declared the factual basis of an expert’s opinion and the application of the expert’s methodology to the facts of the case to be matters of weight for juries to evaluate and not admissibility considerations for the court to decide.  Second, some courts did not assess expert testimony under the preponderance of the evidence burden of production that applies to Rule 702 inquiries, but instead relied on characterizations of Rule 702 as being a “liberal” standard or “presuming admissibility.”  Finally, a number of judges allowed experts to overstate the conclusions that their methodology will actually support, resulting in expressions of a degree of confidence in the experts’ conclusions that go beyond what reliable science will allow.

Each of these misunderstandings reflects a perspective that is legally flawed.  The new Rule 702 amendments seek to correct these errors.

The discussion that follows examines the corrective effects of the 2023 amendments and how these changes to the Rule impact court and litigant practices.

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