What's Driving Increases in the Cook County Jail Population?

Dashboard with data on Illinois prison populations, admissions, releases, and MSR populations from 2018 to the present.

Illinois Prison Dashboard

A one-page summary of the past year of learning, teaching, collaborating, presenting, and publishing at the Center for Criminal Justice. 

2024-25 Year in Review

Contents: the Cook County Dashboard, Detention Hearings Under the PFA, Gender Violence Survey of Incarcerated Women, Year in Review

Front & Center #10: The Cook County Criminal Justice Data Dashboard: Bookmark It!

A dashboard populated with data on Cook County crime, arrests, criminal case filings and dispositions, sentences, jail populations, probation populations, and prison and parole populations.

Cook County Criminal Justice Data Dashboard 

Make of It What You Will: A Jump in Women’s Prison Admissions?

An updated look at Illinois prison returns for technical violations through June 30, 2024. 

Returns to Prison for Technical MSR Violations in Illinois: An Updated Look

Updated findings from our evaluation of a deferred prosecution program operated by the Winnebago County (Illinois) State’s Attorney’s Office.

An Evaluation of the Winnebago County State’s Attorney’s Office Deferred Prosecution Program: 2025 Update

Contents: results of a large-scale survey of people in Illinois prisons regarding their post-release housing needs; what we’ve been learning from Illinois defenders as they try to cope with an array of new pretrial responsibilities imposed by the Pretrial Fairness Act; some new work with Winnebago County, a longtime partner of ours; and a small celebration of CCJ’s first decade. 

Front & Center #12: December 2025

A one-page summary of the first ten years of learning, teaching, collaborating, presenting, and publishing at the Center for Criminal Justice. 

Center for Criminal Justice Decade in Review, 2015-2025

A dashboard populated with data on Winnebago County crime, arrests, criminal case filings, sentences, jail populations, probation populations, and prison and parole populations.

Winnebago County Data Dashboard

Findings from a survey of people nearing release from Illinois prisons sheds light on the complex housing needs of this population. 

Coming Home? Assessing the Housing Needs of People Nearing Release from Illinois Prisons

Preliminary Findings from a Process Evaluation of the Lake County Juvenile Probation RYSE Program 

Contents: PFA coverage, PFA impact on jail populations, a new Illinois Prison Dashboard

Front & Center Newsletter #11: Loyola's 15 Minutes of Fame

A new analysis shows that pretrial jail population numbers in Illinois have rebounded since the first few months of the Pretrial Fairness Act. 

Pretrial Detention and Supervision Under the PFA

Contents: Truth in Sentencing in Illinois, Rural Drug Usage, Emerging Adults, New Projects

Front & Center #9: Truth in Sentencing and Illinois Prisons

This analysis of Illinois Department of Corrections population data explores the lasting impact of Truth in Sentencing laws enacted in the late 1990s and early 2000s.

Truth in Sentencing and Illinois Prisons

Contents: The PFA in Rural Illinois, Improved Access to CCJ Publications, New Work

Front & Center #8: How is Pretrial Reform Working Out in Rural Illinois?

This research brief, based primarily on analysis of a year's worth of pretrial data from 78 Illinois counties (6 urban and 72 rural), explores how   rural counties’ experiences under the Pretrial Fairness Act differ, both from   one another and from those of urban counties.

Pretrial Reform in Rural Illinois

Case Processing in Three States

Beginning September 18, 2023, the Pretrial Fairness Act fundamentally altered pretrial practices in Illinois. What can we say about the workings and effects of the new law at the one-year point?

The First Year of the Pretrial Fairness Act

Contents: The First Year of the PFA in Illinois

Front & Center #7: The PFA at One Year

This new analyses of Illinois arrest and prison admission data by age documents a steep statewide decline since 2010 in arrests and prison sentences for individuals 18-24.

Emerging Adults in Illinois: Recent Trends and Patterns in Arrests and Prison Sentencing

Two-year findings and recommendations from our evaluation of a deferred prosecution program in Winnebago County, Illinois.

An Evaluation of the Winnebago County State’s Attorney’s Office Deferred Prosecution Program: Year Two Report

Contents: Post-Prison Arrests in Illinois; Gun Possession Sentencing; A Reentry Housing Evaluation; New Data Tools; The Center's Year in Numbers

Front and Center #6: Recidivism and COVID, New Data Tools, the Year in Numbers

The numbers that sum up the past year of learning, teaching, traveling, collaborating, presenting, and publishing at the Center for Criminal Justice. 

2023-24 Year in Review

The 40% decline in Illinois' prison population from 2010 to 2023 was due to a broad statewide shift in felony sentencing practices.

Statewide Shifts in the Use of Prison and Probation Sentences

In cooperation with the John Howard Association (JHA), we created an interactive dashboard that allows users to explore responses to the Measuring the Quality of Prison Life (MQPL) survey, which was administered to people held in 28 Illinois Department of Corrections facilities in 2022-23.

MQPL Survey Dashboard

This report examines recent trends and patterns in post-prison recidivism in Illinois, and includes an analysis of recidivism among those released during the COVID-19 pandemic.

Recidivism Patterns Among Those Released from Prison in Illinois

This research brief updates and expands the Center’s prior research to examine trends and patterns in prison sentencing and time served for illegal gun possession in Illinois. 

Sentences to Prison in Illinois for Illegal Possession of a Firearm

An evaluation showed that returning residents who participated in the pilot (RHDP) had a recidivism rate that was roughly a third lower than a comparison group of individuals released from prison at roughly the same time.

Illinois Reentry Housing Demonstration Program - Process Evaluation

A Power BI vizualization looking at felony sentences in IL

Illinois Sentencing Dashboard: Prison and Probation Sentences

Contents: Hearing Practice Under the PFA; Detention in Domestic Violence Cases; the Chicago Incident Tracker; a new District Attorney Data Dashboard; Introducing Loyola Students to the Real World of Criminal Justice Reform

Front and Center #5:       The PFA in the Courtroom

How has the Pretrial Fairness Act affected day-to-day practice in Illinois courtrooms? 

Some Observations: Pretrial Hearings Before and After the PFA

Examining the Frequency and Outcomes of Motions to Detain in Cook, DuPage, Kane, and McHenry Counties

Petitions to Detain for Domestic Violence Cases

Chicago Incident Tracker

Contents: Jail Trends After the PFA; Measuring the Quality of Life in Prison; Deferred Prosecution

Front and Center #4: What's Going On in Illinois Jails?

Tracking the Illinois Jail Population after the PFA implementation.

Illinois Jail Population Tracker

We compared jail booking and average daily jail population data for the periods immediately before and after the effective date of the Illinois Pretrial Fairness Act, and found that both bookings and average populations had declined beyond what would have been expected due to normal seasonal fluctuations.

Short-Term Trends in Jail Bookings & Populations After the Pretrial Fairness Act

We reported interim findings from an ongoing evaluation of a deferred prosecution program in Winnebago County, Illinois.

Evaluating a Prosecutor-Led  Pretrial Diversion Program in Winnebago County: Interim Report

In collaboration with the John Howard Association (JHA) of Illinois, we analyzed results from a large-scale survey on the quality of life in Illinois prisons. 

Measuring Culture and Climate in Illinois Prisons

Contents: The JCOIN Project; Trends in Women's Imprisonment; Integrating Research and Teaching; A New Cook County Jail Tracker

Front and Center #3:  Research That Informs and Supports Practice

This brief describes Loyola's work helping expand treatment access for people returning from Illinois prisons, as part of the Justice Community Opioid Innovation Network (JCOIN).

Supporting Successful Reentry Through Opioid Abuse Treatment

An updated analysis of prison population data traces recent declines in the incarceration of women in Illinois.

Recent Trends in Illinois Women’s Prison Population 

A data tool that tracks the daily Cook County Jail and Community Corrections population.

Tracking the Cook County Jail and Community Corrections Population

Contents: The PFA's First Month; a War on Guns; Violence Prevention in a City of Mourning

Front & Center #2: Observations on the PFA's First Month

Loyola’s Center for Criminal Justice is collaborating with Winnebago County and the City of Rockford on a process and impact evaluation of their local Focused Deterrence Program. 

Focused Deterrence Project 1st Year Brief 

Limited data in the first month of implementation suggest that the PFA may be reducing jail usage, but the impact varies from county to county.

What Effect is the PFA having on Pretrial Jail Usage?

A little over a month after the Illinois Pretrial Fairness Act went into effect, we summarize some preliminary observations on the rollout of the new law.

Doing Without Cash Bail in Illinois: The PFA’s First Month

Contents: Recap of PFA Evaluation Findings to Date; Assessing Quality of Life in Illinois Prisons; Prosecutorial Performance Indicators Meeting

Front & Center #1:  Abolishing Cash Bail in Illinois--What You Missed

Professors Don Stemen and David Olson of Loyola University Chicago CCJ examine whether crime has increased in places that have implemented bail reforms since 2017.

Is Bail Reform Causing an Increase in Crime?

We explore how important monetary bail is as a source of restitution for victims of crime and whether the elimination of monetary bail will have the unintended consequence of reducing compensation for victims.

Will Eliminating Monetary Bail Deprive Crime Victims of Compensation?

Practitioner interviews suggest that bail is imposed for a broader range of purposes than is usually articulated, at least in public. Our analyses of available data show that bail’s practical results are different from those that are widely assumed. And our conversations with defendants—people who know the pretrial system from inside—have surfaced beliefs and perceptions about bail that are both disturbing and important.

Paying in Advance: Perceptions of Monetary Bail in Illinois

The Center collaborated with the Illinois Department of Corrections’ Planning and Research Unit to examine the number, characteristics, and circumstances of individuals on Mandatory Supervised Release (MSR, or “parole”) who violated conditions of their release and were returned to prison (i.e., “technical violators”).

Examining The Impact and Reasons for Technical Violations of Mandatory Supervised Release on Prison Admissions in Illinois

Illinois Practitioners on Pretrial Detention and its Uses

A Little Bit of Time in Jail

Some Insights from Illinois Practitioner Interviews

Why Hold On to Cash Bail?

Process evaluation of an Effective Practices in Community Supervision (EPICS) program in Cook County, Illinois.

Effective Practices in Community Supervision (EPICS): Examining Key Program Processes and Outcomes of the EPICS Pilot Program in Cook County, Illinois

Examines plea negotiations in Milwaukee and St. Louis County.

Exploring Plea Negotiation Processes and Outcomes in Milwaukee and St. Louis County

Most people pass through jails, being held for relatively short periods before bonding out—and that includes people charged with the kinds of serious offenses that are designated “detainable” under the PFA.

Cash Bail Detains People Charged with Serious Offenses—But for How Long?

Under the current cash bail system, most people - even people charged with serious crimes - do not await trial in jail.

How Much Pretrial Detention Does Cash Bail “Buy”?

This tool presents data comparing existing Cook bond decisions with the new PFA detainable groups.

How Bond Decisions Will Change in Cook County Under the PFA

Examining the number and percent of individuals receiving individual-recognizance bonds (I-Bonds), cash or deposit bonds (C/D-Bonds), and No Bail for offenses that will be detainable or non-detainable under the PFA.

Estimating the Impact of the Pretrial Fairness Act: Bond Decisions in Lake County

A detailed analyses of 1,836 new cases that went through bond court in Lake County, Illinois, from March 1 to December 31, 2021.

Examining Bond Court Outcomes & Pretrial Release in Lake County, Illinois

Observations in Cook, Lake, Winnebago, and McLean Counties

Estimating the Impact of the Pretrial Fairness Act: Bond Court Hearings in Cook, Lake, Winnebago, and McLean Counties

An examination of case screening and assessment practices across prosecutors’ offices in 15 jurisdictions.

Reject or Dismiss? A Prosecutor's Dilemma

Bond Decisions in Cook County

This report examines trends in the number of individuals admitted to jail pretrial or formally supervised under pretrial supervision in the community. 

Individuals Held in Pretrial Detention and Under Pretrial Supervision in the Community

The Volume & Characteristics of Arrests Eligible for Detention

This report by researchers at the Center for Criminal Justice Research, Policy, and Practice at Loyola University Chicago analyzes the impact of bond reform in Cook County on felony bond court decisions, pretrial release, and crime.

Dollars and Sense In Cook County

Interactive report examining racial disparities and prosecutorial decision making in the Ninth Circuit Solicitor’s Office in Charleston County, South Carolina.

Disparity and Prosecution in Charleston, SC

A detailed examination of race and diversion across prosecutors’ offices in 4 jurisdictions.

Race and Prosecutorial Diversion: What We Know and What Can Be Done

This report analyzes defendant characteristics and trends in sentences for felony gun possession offenses in Illinois.

Sentences Imposed on Those Convicted of Felony Illegal Possession of a Firearm in Illinois

Technical Report to Reducing Revocations Challenge: The Cook County (Chicago) Adult Probation Department and Loyola University Chicago Action Research Team Final Report

Technical Report to Reducing Revocations Challenge

This report analyzes defendant characteristics and trends in arrests for gun possession offenses in Lake County, Illinois.

Arrests in Lake County for Illegal Possession of a Firearm

Examines the prevalence and factors that influence probation revocation in Cook County, Illinois.

Reducing Revocations Challenge: The Cook County (Chicago) Adult Probation Department and Loyola University Chicago Action Research Team Final Report

This report analyzes defendant characteristics and trends in arrests for gun possession offenses in Cook County, Illinois.

Arrests in Cook County for Illegal Possession of a Firearm 

This report profiles Lake County's criminal justice system and outlines major trends in arrests, prosecutions and sentencing through 2019.

Lake County’s Criminal Justice System: Trends and Issues Report 3rd Edition

This report, produced in collaboration with the Winnebago County Criminal Justice Coordinating Council, profiles the county's criminal justice system and outlines major trends in arrests, prosecutions and sentencing through 2019.

Winnebago County’s Criminal Justice System: Trends and Issues Report 3rd Edition

This report analyzes defendant characteristics and trends in arrests for gun possession offenses in Illinois.

Arrests in Illinois for Illegal Possession of a Firearm

Process evaluation of a Focused Deterrence Intervention pilot program.

Rockford Focused Deterrence Initiative Research Report

A profile of Cook County's criminal justice system, with an examination of recent trends in reported crime, arrests, prosecutions, and sentences. 

Cook County’s Criminal Justice System: Trends and Issues Report 2nd Edition

Comparison of results of two community surveys conducted in connection with planning and implementation of a focused deterrence pilot program in Rockford.

The Rockford Community Perceptions of Crime Survey: Comparison of 2017 and 2019 Results

A detailed exploration of race, ethnicity and case approval, charging, disposition, and sentencing in Cook County, Illinois.

Race, Ethnicity and Prosecution in Cook County, Illinois

Results of a survey of the Rockford community, conducted as part of the planning for a Focused Deterrence Intervention pilot program.

The 2019 Rockford Community Perceptions of Crime Survey: Results

A detailed exploration of race, ethnicity and case approval, charging, disposition, and sentencing in Milwaukee County, Wisconsin.

Race, Ethnicity and Prosecution in Milwaukee County, Wisconsin

Results of a survey of Rockford police officers, conducted as part of the planning for a Focused Deterrence Intervention pilot program.

The Rockford Police Officer Survey: Results

An examination of state and county data on felony sentencing in Illinois, and factors that are associated with various types of sentences.

An Examination of Factors Influencing the Sentencing of Convicted Felons in Illinois

This 2019 issue brief explores data on emerging adults (18- to 25-year-olds) in the Illinois criminal justice system and discusses policy and practice implications.

Emerging Adults and the Illinois Criminal Justice System

This report, produced in collaboration with the McHenry County Criminal Justice Coordinating Council, profiles the county's criminal justice system and outlines major trends in arrests, prosecutions and sentencing during the period from 2010 through 2016.

McHenry County’s Criminal Justice System: Trends and Issues Report 

Research brief exploring Cook County's contribution to the Illinois prison population over the years from the early 1980s to 2018.

The Rise (and Partial Fall) of Adults in Illinois’ Prisons from Cook County

Summarizes findings from an on-line survey of 275 prosecutors and in-depth interviews with 78 prosecutors in 4 jurisdictions, exploring prosecutorial attitudes, priorities and goals.

Prosecutorial Attitudes, Perspectives, and Priorities: Insights from the Inside

Detailed guide to accessing juvenile justice data in Illinois.

Juvenile Justice Data Guide: State-level collection, reporting and availability of juvenile justice data in Illinois

This report, produced in collaboration with the St. Clair County Criminal Justice Coordinating Council, profiles the county's criminal justice system and outlines major trends in arrests, prosecutions and sentencing during the period from 2010 through 2016.

St. Clair County’s Criminal Justice System: Trends and Issues Report

This report, produced in collaboration with the McLean County Criminal Justice Coordinating Council, profiles the county's criminal justice system and outlines major trends in arrests, prosecutions and sentencing during the period from 2010 through 2016.

McLean County’s Criminal Justice System: Trends and Issues Report

Detailed overview and guide to Illinois criminal justice data reporting mandates and data collection mechanisms.

Criminal Justice Data Guide: State-level collection, reporting and availability of criminal justice data in Illinois 

Results of a 2017 survey of the Rockford community, conducted as part of the planning for a Focused Deterrence Intervention pilot program.

The Rockford Community Survey: Results

Research brief describing custodial arrest patterns and trends for men and women arrested in Illinois between 2005 and 2017.

Overall Arrests in Illinois, by Gender 

Research brief describing arrest patterns and trends for men and women arrested in Illinois for property crimes between 2005 and 2017.

Property Crime Arrests in Illinois, by Gender

Research brief describing arrest patterns and trends for men and women arrested in Illinois for drug crimes between 2005 and 2017.

Drug Arrests in Illinois, by Gender

Research brief describing custodial arrest patterns and trends for men and women arrested for violent crimes in Illinois between 2005 and 2017.

All Posts

What's Driving Increases in the Cook County Jail Population?

Illinois Prison Dashboard

2024-25 Year in Review

Front & Center #10: The Cook County Criminal Justice Data Dashboard: Bookmark It!

Cook County Criminal Justice Data Dashboard