Good Cop, Bad Cop: Delegating Interrogations

A decision-maker who aims to find the truth from a suspect delegates to an interrogator with possibly misaligned preferences. The ideal interrogator is always misaligned: sometimes nicer, sometimes tougher. The decision-maker can further improve by conditioning the delegation on the evidence, which is her private information, appointing a nice interrogator when the evidence is weak and a tougher interrogator when the evidence is strong. Dynamic, endogenous, conditional delegation can credibly convey information about the strength of the evidence and implement the overall optimum with full commitment. Moreover, the decision-maker can then retain authority over decisions by relying on the interrogator’s recommendations.