An expert who ignored studies was excluded by the district court, but the Court of Appeals found an abuse of discretion, holding that the sufficiency of an expert’s basis is a question of weight and not admissibility.[13] These rulings elevate form over substance by halting the gatekeeping inquiry at an irrelevant, high level of abstraction, and finding that the challenged expert witness was doing something “sciencey,” which is good enough for government work. [read post]