 In the Late Roman Empire the citizens performed opera publica in lieu of paying taxes; often it consisted of road and bridge work.Roman landlords could also demand some days' labour from their tenants, and also from the freedmen; in the latter case, the work was called opera officiales.Public works were an important department, and the Roman censors were entrusted with the expenditure of this department's public money, though the actual payments were no doubt made by the quaestors.