| Abstract: | It is natural to suppose that a prosecutor's conviction rate—theratio of convictions to cases prosecuted—is a sign ofhis competence. Prosecutors, however, choose which cases toprosecute. If they prosecute only the strongest cases, theywill have high conviction rates. Any system that pays attentionto conviction rates, as opposed to the number of convictions,is liable to abuse. As a prosecutor's budget increases, he allocatesit between prosecuting more cases and putting more effort intoexisting cases. Either can be socially desirable, dependingon particular circumstances. We model the tradeoffs theoreticallyin two models, one of a benevolent social planner and one ofa prosecutor who values not just the number of convictions butthe conviction rate and unrelated personal goals. We apply themodel to U.S. data drawn from county-level crime statisticsand a survey of all state prosecutors by district. Convictionrates do have a small negative correlation with prosecutorialbudgets, but conditioning on other variables in regression analysis,higher budgets are associated both with more prosecutions andhigher conviction rates. |
