SearchSystems Editorial

Reviewed and updated October 9, 2026 by the SearchSystems.net editorial team. The arrest counts are the ones each agency reported to the FBI, as the FBI held them on October 8, 2026. The jail figures are from the Vera Institute of Justice's Incarceration Trends data. Every office link was opened and checked against the office's own site between September 23, 2026 and October 4, 2026.

About this guide

St. Clair County, Illinois, has about 251,000 residents (2024 Census Bureau estimate), and arrests there are reported to the FBI by the St. Clair County Sheriff's Office, 22 city agencies and three campus, state or other agencies. An arrest leaves the same records whoever makes it: the arresting agency's report, the record of anyone held at the county jail, and, if the State's Attorney files charges, a case in the Circuit Court of St. Clair County. This guide says who keeps each one, what it costs and who may see it, with the arrest counts each agency reported.

This guide covers who makes arrests, how many arrests, booking and the jail, finding an arrest, copies, cities and common questions.

Related guides: St. Clair County public records, Illinois arrest records, Illinois inmate search and Illinois criminal records.

Who Makes Arrests in St. Clair County

The St. Clair County Sheriff's Office is the county agency that reports arrests to the FBI for St. Clair County. It reported 248 arrests for 2025.

The FBI lists 22 cities in St. Clair County with a reporting agency of their own, with the Census population and what each reported, the largest twelve first; the rest are named in the cities section below:

  • Belleville, 40,560 residents: 929 arrests reported for 2025.
  • O'Fallon, 32,169 residents: 744 arrests reported for 2025.
  • East St. Louis, 17,808 residents: 0 arrests reported for 2019.
  • Cahokia Heights, 17,052 residents: 1,152 arrests reported for 2025.
  • Fairview Heights, 16,115 residents: 1,028 arrests reported for 2025.
  • Shiloh, 14,754 residents: 112 arrests reported for 2025.
  • Swansea, 14,445 residents: 182 arrests reported for 2025.
  • Mascoutah, 9,118 residents: 54 arrests reported for 2025.
  • Lebanon, 4,628 residents: 3 arrests reported for 2025.
  • Freeburg, 4,518 residents: 0 arrests reported for 2024.
  • Caseyville, 4,395 residents: 0 arrests reported for 2025.
  • Millstadt, 3,957 residents: 91 arrests reported for 2025.

A city on that list is reported separately whether the officers are the city's own or the sheriff's under contract; the FBI's list does not say which.

The Columbia Police Department, the New Baden Police Department, the Collinsville Police Department and one more are each listed by the FBI across several counties including St. Clair County, so their arrests are not broken out for St. Clair County here.

The FBI's agency list also places these agencies in St. Clair County: Alton and Southern Railway and Union Pacific Railroad in St. Clair County (other); Southwestern Illinois College (campus police).

How Many Arrests Each Agency Reports in St. Clair County

The FBI publishes every agency's monthly arrest counts on the Crime Data Explorer. These are the full-year totals, all offenses, as the FBI held them on October 8, 2026; a year with months missing or not reported is left out.

  • East Carondelet: 1,152 for 2025, 1,152 for 2024, 1,146 for 2023, 1,132 for 2022, 919 for 2021 and 1,146 for 2020.
  • Cahokia Heights: 1,152 for 2025, 1,152 for 2024, 1,146 for 2023, 1,132 for 2022, 919 for 2021 and 1,146 for 2020.
  • Fairview Heights: 1,028 for 2025, 850 for 2024, 741 for 2023, 684 for 2022 and 449 for 2021.
  • Belleville: 929 for 2025, 933 for 2024, 587 for 2023 and 561 for 2022.
  • O'Fallon: 744 for 2025, 669 for 2024, 863 for 2023, 728 for 2022 and 471 for 2021.
  • St. Clair County Sheriff's Office: 248 for 2025, 323 for 2024, 418 for 2023 and 211 for 2022.
  • Fairmont City: 194 for 2025 and 136 for 2024.
  • Swansea: 182 for 2025, 234 for 2024, 184 for 2023, 236 for 2022 and 179 for 2021.
  • Sauget: 160 for 2025 and 104 for 2024.
  • Shiloh: 112 for 2025, 70 for 2024, 88 for 2023 and 58 for 2022.
  • Millstadt: 91 for 2025, 96 for 2024, 44 for 2023, 31 for 2022, 52 for 2021 and 0 for 2020.
  • Mascoutah: 54 for 2025, 45 for 2024, 63 for 2023, 53 for 2022, 0 for 2020 and 0 for 2019; 2021 is missing months.

Together, the 17 agencies with all twelve months of 2025 on file reported 6,114 arrests that year. The same agencies with both 2025 and 2024 complete reported 6,114 in 2025 against 5,839 in 2024, up 4.7 percent.

Through June 2026, the 14 agencies with every month so far on file reported 2,705 arrests, against 2,851 in the same months of 2025.

Freeburg reported only part of 2025 (11 months) and is left out of the totals.

Booking: Where People Arrested in St. Clair County Are Held

The county jail is where a person arrested in St. Clair County and kept in custody ends up, whichever agency made the arrest, though a city department may hold someone in its own cells first and a person cited and released at the scene is never booked. The jail's record of each person held, with the charges, is a public record of the arrest, and once the person is released or sentenced the record continues in the court file.

On an average day in 2021 the jail held about 450 people, up from about 350 in 2019. Its rated capacity in 2019, the last year with a capacity figure, was 418 beds, and it ran at 84 percent of it that year. The figures are from the Vera Institute of Justice's Incarceration Trends data.

SearchSystems opened and checked the jail page of the St. Clair County Sheriff's Office at co.st-clair.il.us/departments/sheriffs-department (page title: Sheriff's Department | Departments | St. Clair), phone (618) 277-3505, which answered when SearchSystems opened it on October 4, 2026.

A person sentenced to prison serves the sentence in a facility of the Illinois Department of Corrections, whose inmate locator is at idoc.illinois.gov/offender/inmatesearch.html.

How to Find Out About an Arrest in St. Clair County

For St. Clair County the place to look is the State's Attorney, which decides whether an arrest becomes a charge (its page is at co.st-clair.il.us/departments/states-attorney, phone (618) 277-3892).

Illinois is one of the states that lets anyone look up another person's statewide criminal history: conviction information is public under the Uniform Conviction Information Act, through the Illinois State Police. That record shows what agencies reported to the state, which is wider than one county's court index but can lag it.

Getting a Copy of an Arrest Record in St. Clair County

An arrest report belongs to the agency whose officer wrote it, and that agency releases it, not the court or the jail. Under the Illinois Freedom of Information Act the agency must answer within 5 business days, with one 5-day extension, and it may charge copying only after the first 50 pages.

  • An arrest by the St. Clair County Sheriff's Office: ask its records unit, reached through the office at (618) 277-3505.
  • An arrest in Belleville, O'Fallon, East St. Louis, Cahokia Heights, Fairview Heights, Shiloh or another of the cities listed above: the records unit of the agency that reports for that city; the city guides linked above name each city's records office.
  • An arrest by Alton and Southern Railway, Union Pacific Railroad in St. Clair County or Southwestern Illinois College: the records office of the agency involved.
  • A defendant who has been charged gets the report through the case: the State's Attorney, (618) 277-3892, handles discovery for pending cases.
  • Any county record that is not posted: the county records request page SearchSystems verified is at stclaircountyil.justfoia.com (page title: St. Clair County, IL Public Portal | JustFOIA).
  • Your own statewide record: a name-based or fingerprint-based request to the Illinois State Police.

Cities in St. Clair County: Who Reports the Arrests

The FBI lists a separate arrest reporting agency for 22 of the 25 cities in St. Clair County: the twelve named above and Smithton, Dupo, Washington Park, Fairmont City, New Athens, Marissa, Brooklyn, East Carondelet, Summerfield and Sauget. St. Libory, Lenzburg and Fayetteville have no separate reporting agency in the FBI's list.

Wherever in the county the arrest happens, a person kept in custody goes to the county jail and the case goes to the Circuit Court of St. Clair County.

SearchSystems has a guide to the offices of these cities in St. Clair County, with the 2024 Census Bureau population; a city with its own arrest records guide opens there:

Frequently Asked Questions

How many arrests are made in St. Clair County each year?

East Carondelet reported 1,152 arrests to the FBI for 2025, and the 17 agencies with every month of 2025 on file reported 6,114 between them.

How do I find out if someone is in jail in St. Clair County?

Ask the St. Clair County Sheriff's Office at (618) 277-3505; its jail page SearchSystems verified is at co.st-clair.il.us.

Where are people arrested in St. Clair County booked?

Those kept in custody go to the county jail, run by the St. Clair County Sheriff's Office; a person cited and released at the scene is not booked.

Are arrest records public in St. Clair County?

The court files of criminal cases are public, and so is the statewide criminal history kept by the Illinois State Police: conviction information is public under the Uniform Conviction Information Act. The arrest report itself is released by the agency that made the arrest, under the Illinois Freedom of Information Act.

How do I get a copy of an arrest report in St. Clair County?

From the agency that made the arrest: the St. Clair County Sheriff's Office for its own arrests, or the agency that reports for the city where it happened. Under the Illinois Freedom of Information Act the answer is due within 5 business days, with one 5-day extension; the county records request page SearchSystems verified is at stclaircountyil.justfoia.com.

Is this the official St. Clair County website?

No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official county, court and state offices described above and does not hold records, charge for them or take requests.