The 30-year anniversary of Daubert v. Merrell Dow Pharmaceuticals Inc. (509 U.S. 579) will be coming up in 2023. This decision officially made federal judges the “gatekeepers” of expert evidence against “junk science.” Landmark case In 1993, Daubert established a two-pronged test for admissibility under Rule 702 of the Federal Rules of Evidence: An expert’s methodology must be 1) reliable, and 2) relevant. This case also identified four nonexclusive factors to consider in determining the reliability of an expert’s theory or technique: Has it been tested, and can it be tested? Has it been subject to peer review or publication? What’s its known or potential error rate? Is it generally accepted in the relevant scientific or technical community?   The discounted cash flow method is an example of a...