Evidence Suppression by Prosecutors: Violations of the Brady Rule

We develop a model of individual prosecutors (and teams of prosecutors) to address the incentives for the suppression of exculpatory evidence. Our model assumes that each individual prosecutor trades off a desire for career advancement (by winning a case) and a disutility for knowingly convicting an innocent defendant. We assume a population of prosecutors that is heterogeneous with respect to this disutility, and each individual’s disutility rate is their own private information. A convicted defendant may later discover exculpatory information; a judge will then void the conviction and may order an investigation. Judges are also heterogeneous in their opportunity costs (which is each judge’s private information) of pursuing suspected misconduct. We show that the equilibrium information configuration within the team involves concentration of authority about suppressing/disclosing evidence. We further consider the effect of angst about teammate choices, office culture, and the endogenous choice of effort to suppress evidence. (JEL D73, D82, K4)