The Fall of Capital Punishment and the Rise of Prisons: How Punishment Severity Affects Jury Verdicts

This paper studies the effect of punishment severity on jury decision-making using a large archival data set from the Old Bailey Criminal Court in London from 1715 to 1900. We take advantage of three natural experiments in English history, which result in sharp decreases in punishment severity: The offense specific abolition of capital punishment in the 1800s, the temporary halt of penal transportation during the American Revolution, and the abolition of transportation in 1853. Using a difference-in-differences design to study the abolition of the death penalty and pre-post designs to study the temporary and permanent halts to transportation, we find that decreasing expected punishment (especially via the end of the death penalty), had a large and significant impact on jury behavior, generally leading to the jury being ‘harsher’. Moreover, we find that the size of the effect differs with defendants’ gender and criminal history. These results raise concerns about the impartiality of juries as well as the implicit assumption often made when designing and evaluating criminal justice policies today – that the chance of conviction is independent of the harshness of the penalty.