This dashboard presents data on the number of people in Illinois prisons. The number and characteristics of people in prison will reflect trends in sentencing (admissions to prison) and length of stay. Individuals convicted of more violent, more serious crimes are more likely to be sentenced to prison and are sentenced to longer prison terms. Individuals sentenced to prison for more violent, more serious crimes also can be subject to Truth in Sentencing (TIS) guidelines, meaning that they are not eligible to earn time off their sentence for good behavior or for participation in prison programming. While individuals convicted of serious crimes make up a smaller proportion of prison admissions, they account for a larger proportion of people in prison on any given day because their length of stay in prison is relatively long.

Information on prison populations comes from the Illinois Department of Corrections public data portal and is updated quarterly. These data reflect the number of people in prison on the date associated with the end of each quarter (e.g., June 30 for the 2nd quarter).