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Policies and Procedures of the Criminal Justice System

NCJ Number
Junaid Afeef; Lindsay Bostwick; Simeon Kim; Jessica Reichert
Date Published
August 2012
45 pages

This guide provides an overview of the Illinois criminal justice system process.


This guide provides a detailed walkthrough of the adult criminal justice system in Illinois. There are 102 counties in Illinois; each county operates its criminal justice system independently. The Administrative Office of the Illinois Courts oversees probation and court services departments. The Illinois Department of Corrections oversees State prisons, and individuals on mandatory supervised release. Each county's criminal justice system is comprised of a network of State and local entities. These include: Illinois State Police, county sheriff's departments, municipal police departments, university and college police departments, and other law enforcement agencies; circuit clerks, county probation and court services departments; judges, State's attorneys, public defenders, and private attorneys; Illinois Department of Corrections; county jails and municipal lock-ups; private social service organizations that provide crisis intervention, residential placement, employment, counseling, reentry, and other services; and -based and faith-based organizations and coalitions. This report generally follows the flow of an adult criminal case through the criminal justice system. The first section describes arrest procedures following suspected criminal activity. The second section is on the court system, followed by a section on pretrial activities and a section on trial procedures. Proceeding sections detail sentencing procedures and options, corrections, sentence completion. The final section describes the expungement process. Figures and appendixes