The Role of Discretion in the Criminal Justice System

Abstract

Although a substantial body of research suggests that the discretion of actors in the criminal justice system is important, there is disagreement in the existing empirical literature over the specific role of discretion and over the extent to which discretion influences criminal justice outcomes. Studies in this literature generally hypothesize that discretion plays one of two roles: either it serves as the means by which changing broad social norms against crime cause changes in sentencing patterns (with concurrent changes in formal laws reflecting broad social norms but not causing criminal justice outcomes), or it serves as the means by which internal social norms of the criminal justice system prevent the implementation of formal changes in laws.

We reject both of these hypotheses using data on the sentencing of California prisoners before and after the passage of Proposition 8, which provided for sentence enhancements for those convicted of certain "serious" crimes with "qualifying" criminal histories. We find that an increase in the statutory sentence for a given crime can increase sentence length for those who are charged with the crime, and also for those who are charged with factually "similar" crimes, where a "similar" crime is defined as one that has legal elements in common with the given crime. These spillovers are consistent with neither broad social norms nor internal social norms, so we conclude that discretion takes a less-well studied form, which we call "prosecutorial maximization."