# The Impacts of Parole Supervision In Illinois, reducing the period of supervised release for some prisoners from one year to six months reduced the share of parolees who returned to prison within one year by 41–45 percent without affecting crime rates. June 10, 2026 • Research Briefs in Economic Policy No. 487 By Luke Brinkman, Andrew Jordan, and Derek Neal In 2021, Illinois passed the Safety, Accountability, Fairness and Equity-Today Act, commonly known as the SAFE‑T Act. This legislation received significant national attention because it ended cash bail in Illinois and included numerous reforms to the supervision of prisoners upon their release. In Illinois, most exiting prisoners serve a period of mandatory supervised release (MSR), which is similar to parole supervision in other states. The original SAFE‑T Act modified MSR terms for many parolees, and Illinois amended the law on December 6, 2022, creating a natural policy experiment. During the six months preceding this date, the state assigned a large group of released prisoners to one year of supervision. This group contained prisoners sentenced for both serious offenses (Classes 1 and 2) and lesser offenses (Classes 3 and 4). However, starting on January 1, 2023, the state assigned released prisoners in Classes 3 and 4 to six months of MSR. Our research compares the post-release outcomes of Class 3 and 4 prisoners who left prison in the six months prior to the SAFE‑T Act amendment of December 6, 2022, with those who left prison in the first five months of 2023. Our findings reveal that the reform reduced the share of these prisoners who returned to prison within one year by 9–10 percentage points (roughly 41–45 percent). This reduction was almost entirely due to a lower rate of technical revocations of supervision. These revocations do not constitute new criminal convictions; instead, they occur when the Prisoner Review Board determines that a parolee has violated a condition of their supervision. Parolees must adhere to a substantial set of conditions that governs their lives, such as residing in approved residences, allowing parole officers to search their residence on demand, refraining from associating with known gang members or visiting prisoners, and obtaining permission before traveling or changing addresses. Furthermore, our study finds no evidence that the reform affected crime rates among released prisoners. During the first 15 months after parolees exited prison, the reform had no detectable effect on the rates of new felony charges, new felony convictions, or returns to prison for new crimes. These findings may seem counterintuitive: Less supervision reduced revocations, so more parolees remained out of prison and able to commit new crimes. However, the absence of supervision reduced the likelihood of parolees committing crimes, offsetting any increases in crime associated with fewer technical revocations. More research is needed to understand how the absence of supervision could improve behavior among released prisoners, but it is possible that the constraints imposed by the supervision process hinder their ability to find stable housing, secure employment, and address other factors that promote successful post-release transitions. Additionally, longer terms of parole supervision diminish the benefits of lawful behavior because parolees face the ongoing threat of technical revocation. Consider two parolees who exit prison simultaneously: the first faces a six-month term of supervision, while the second faces a two-year term. If both parolees avoid all criminal activity and potential violations of their parole conditions for six months, the first will exit supervision and face no risk of imprisonment as long as they do not commit a new crime. However, the second knows that authorities can return them to prison for technical reasons for another 18 months, even if they do not commit any new crimes. Thus, the reward for six months of perfect behavior is quite different for these two parolees. We also conducted policy simulations to estimate the impact of reducing existing MSR terms for Class 1 through 4 prisoners by half. In line with recent reforms to MSR in Illinois, we did not alter MSR terms for the most serious offenders (Class X), nor did we reduce MSR terms for sex offenders, regardless of class. Our findings indicate that such a reform would reduce the average prison population by roughly 3 percent and likely cause no harm to public safety. The policy implications of our findings are not entirely clear. Some may interpret our findings as a call to reform the rules and procedures governing parole supervision. Others may propose replacing parole supervision with post-release services provided by nonprofits. Illinois already funds private organizations to provide vocational training for former offenders and provides bonuses when program graduates secure stable employment. Illinois and other states could expand these programs and related services. Alternatively, some may argue that Illinois should abolish post-release supervision, as it restricts the liberty of people who have served their prison sentences without enhancing public safety. Overall, our study contributes to a growing body of research demonstrating that existing parole systems increase reincarceration rates through technical violations of supervision conditions without bolstering public safety. For example, California passed legislation in 2011 that prohibits the use of reincarceration as punishment for technical parole violations. Researchers concluded that this policy reduced prison populations, yet they found little evidence of increased crime rates. Since parole populations in the United States have ranged from roughly 650,000 to 850,000 in recent years, these findings warrant the attention of researchers and policymakers. **Note:** This research brief is based on Luke Brinkman et al., “[The Impacts of Parole Supervision](http://www.nber.org/papers/w34663),” National Bureau of Economic Research Working Paper no. 34663, February 2026. ##### About the Authors ##### Luke Brinkman Washington University in St. Louis ##### Andrew Jordan Washington University in St. Louis ##### Derek Neal University of Chicago [![Creative Commons License](/build/cato_2020/images/creative-commons.svg)](http://creativecommons.org/licenses/by-nc-sa/4.0/) This work is licensed under a [Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License](https://creativecommons.org/licenses/by-nc-sa/4.0/).