Of Illinois’ almost 40,000 inmates housed in state Department of Corrections facilities, a few dozen of them might be eligible for release if the recreational marijuana bill becomes law.
According to the Illinois Department of Corrections, as of April 30, 2019, there were 36 inmates being held on Class Four cannabis charges.

The recreational marijuana bill that passed the General Assembly would expunge some criminal records relating to cannabis charges.
You have to meet the following criteria to be eligible for expungement.
Only non-violent offenders guilty of possessing less than 30 grams of cannabis can be pardoned by the governor.
Those requests don’t need to be initiated by the offender. They are automatic.
Non-violent offenders guilty of possessing more than 30 grams but less than 500 grams of cannabis can petition to have their charges thrown out.
IDOC said they can’t say with certainty if the 36 inmates in their custody fit the criteria for release.