Selective Incapacitation

• NCJ Number: 86888
• Author(s): P W Greenwood; A Abrahamse
• Date Published: 1982
• Length: 150 pages
• Grant Number(s): 79-NI-AX-0055
• Sponsoring Agency: National Institute of Justice (NIJ); US Dept of Justice NIJ Pub
• Corporate Author: Rand Corporation
• Sale Source: Rand Corporation; National Institute of Justice/
• Language: English
• Country: United States of America

Annotation

Self-reported data from prison and jail inmates demonstrates that selective incapacitation strategies may produce significant reductions in crime without increasing the total number of offenders incarcerated.

Abstract

The principal focus of this research was the estimation of the rate at which individual offenders commit crime and modeling the effects of sentencing policies on their time at risk. For incapacitation analysis, the sentencing policy for any specified group of offenders can be described by three parameters: (1) the probability of arrest and conviction, (2) the probability of incarceration given conviction, and (3) the expected sentence length. The expected or average sentence for any one crime is the product of these factors. Given certain assumptions, it can be shown that the amount of crime offenders commit under a sentencing policy, expressed as a fraction of the amount they would commit if they were never incarcerated, is 1 divided by 1 + cqJS, where qJS is the product of the aforementioned three parameters and c is the average rate of the crime being analyzed. This study surveyed 2,100 male prison and jail inmates in California, Michigan, and Texas in 1977 to determine information on prior criminal activity, drug use, employment, juvenile history, and contacts with the criminal justice system. Subjects were compared only on their robbery or burglary offense rates. For California and Texas inmates, the study estimated the impacts of a number of selective policies that extended terms for high-rate offenders and reduced terms for low-rate offenders. Incapacitation effects in Michigan could not be analyzed. The data show a wide variation in individual offense rates and that the factors associated with higher rates of recidivism are also associated with higher rates of offending. Finally, the findings show that selective incapacitation strategies may produce significant reductions in crime without increasing the total number of offenders incarcerated. Issues in the research design and the findings are discussed. Tabular data and 72 references are provided.