Illinois Counties With the Most Registered Sex Offenders

According to, there are 21.63 registered sex offenders for every 10,000 people in Illinois. Based on Illinois' population, that is nearly 28,000 registered sex offenders in the state. It is slightly more than last year's 21.33 per 10,000 people, both of which are more dense than the national average of 14.3 offenders per 10,000 people.

The registry is governed by Illinois laws 730 ILCS 152/115 (a) and (b), which mandates that the Illinois State Police maintain a database of where registered sex offenders live throughout the state. Offenders who have been convicted of committing or attempting to commit certain crimes (or found not guilty by reason of insanity) must register upon their release from prison and check in with authorities about their where they live and what they're up to. (Of course, there might be other people living in communities who are dangerous who are not registered, and in the U.S. there are nearly 22,000 registered sex offenders whose whereabouts are unknown.)

Those crimes include acts such as:

  • Sexual Exploitation of a Child
  • Child Pornography
  • Criminal Sexual Assault
  • Criminal Sexual Abuse
  • Permitting Sexual Abuse of a Child

From the Illinois Sex Offender Registry website:

A sex offender must register in person annually for a period of 10 years. The 10-year registration period will start upon conviction for those offenders sentenced to probation. Those offenders sentenced to the Illinois Department of Corrections, another state's department of corrections, or federal corrections must register for 10 years from final parole, discharge, or release.

There are some areas in Illinois in which more registered sex offenders live than others.

Here are five Illinois counties with some of the most registered sex offenders per capita in the state:

10. Clay 26.03

9. Franklin 26.06

8. Massac 26.68

7. DeWitt 27.17

6. Union 27.53

See which five counties have the most registered sex offenders per capita in Illinois and which counties have the fewest registered sex offenders per capita in Illinois at Reboot Illinois.

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