An experimental comparison of adversarial versus inquisitorial procedural regimes

This article reports the results of a multiyear series of economicexperiments comparing the two dominant types of legal proceduresused in adjudication: (1) the 'adversarial' model of party-controlledprocedure versus (2) the 'inquisitorial' model of judge-controlledprocedure. The principal finding is that the relative fact-findingefficiency of the two systems, in terms of both the 'revelation'of hidden facts and the 'accuracy' of decision, depends significantlyupon the information structure. Under a 'private' informationstructure, inquisitorial procedure is relatively more efficient,whereas under a 'correlated' information structure, adversarialprocedure is relatively more efficient.