The impact of state sentencing policies on the U.S. prison population

This article examines the aggregate effects of neoclassical sentencing reforms on three often contested outcomes of these reforms. The rate of new court commitments, the average length of time inmates serve, and prison population rates across the fifty U.S. states and the District of Columbia are examined. Data from 1973 to 1998 across these jurisdictions are analyzed using hierarchical multivariate linear models (HMLM). Results show that on the aggregate, sentencing reforms are not directly related to changes in state prison populations; however, abolition of parole is negatively associated with state prison population rates. Two types of sentencing reforms, the voluntary sentencing guidelines and the 'three-strikes' laws are indirectly related to changes in prison populations and have opposite influences on rates of new court commitments. Of six sentencing practices examined, not one is associated with length of incarceration. These results do not support the contention that neoclassical changes to the nation's sentence policies account for the rapid increase in the state prison populations between the early 1970s and late 1990s.