Credible plea bargaining

This paper demonstrates that the role of plea bargaining as a screening device depends neither on the commitment to trial nor on the commitment to some prosecutorial expenditures. In a situation where a prosecutor cannot commit to trial nor spends resources to obtain more evidence, I find a semi-separating equilibrium in which the prosecutor makes an offer that can be accepted only by the guilty defendant with some positive probability, and then, if the offer is rejected, he proceeds to trial, based on his updated belief. I also consider the prosecutor’s decision to choose the amount of (per capita) prosecutorial expenditures both in the commitment case and in the noncommitment case, and argue that an increase in the per capita expenditure may reduce the gross expenditures on prosecution by lowering the chance of trial.