Between 2010 and 2023, the number of people in Illinois prisons fell nearly 40 percent, reaching the lowest level since 1991. The general consensus is that the decline in the prison population is due to broad changes in sentencing practices, especially the increased use of community supervision (probation). A shift in thinking regarding sentencing goals, the increased availability of community-based options like probation, and concerns over the cost of incarceration have led to these significant changes.
A number of specialized alternative treatment programs that keep those convicted of a crime out of prison have been seen across the state. Jail-based programs, police-led deflection efforts that divert people into treatment, specialized treatment courts, and enhanced probation services are all making substantial contributions to divert people from prison whenever possible. The state has also dedicated funding to programs like Adult Redeploy Illinois.