Adversarial bias, litigation, and the Daubert test: An economic approach

The last few decades have seen a dramatic shift in the admissibility of expert testimony in American courtrooms from a laissez-faire approach to a strict standard for admissibility, often called the Daubert test. The implicit rationale behind such a stringent standard for admissibility is the trier of fact's vulnerability to adversarial bias, which many legal scholars and practitioners assume to be rampant. Employing a standard litigation model in the literature, I demonstrate that client–expert relationships may not always exhibit adversarial bias and that a litigant may voluntarily present neutral expert testimony under certain situations. I also show that a litigant is more likely to deploy hired guns if the litigation environment is more favorable to his cause. In particular, the burden of proof assignment and the court's prior belief are shown to influence adversarial bias.