Reviewed and updated October 11, 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. Every office link was opened and checked against the office's own site between September 23, 2026 and October 11, 2026.
St. Clair County, Illinois, has about 251,000 residents (2024 Census Bureau estimate). Its court cases are filed in the Circuit Court of St. Clair County, and the file of each case, kept by the Circuit Clerk, is the public record of it. This guide says which court hears what, where to look a case up and who keeps the files.
This guide covers the courts, the records page, criminal cases, kinds of files, directory links, cities and common questions.
Related guides: St. Clair County public records, St. Clair County arrest records, St. Clair County warrants, St. Clair County inmate search, St. Clair County criminal records, Illinois arrest records and Illinois inmate search.
The Courts That Hear Cases from St. Clair County
In St. Clair County, the Circuit Court of St. Clair County hears every civil, criminal, family, probate, traffic and juvenile case.
Divorces go to the Circuit Court's domestic relations division, and the file stays with the Circuit Clerk.
The Circuit Clerk keeps the files, and a copy of anything in a file comes from that office, under the court's own rules rather than the Illinois Freedom of Information Act.
Looking Up a Case from St. Clair County
The court records page SearchSystems verified for the county is at co.st-clair.il.us/WebDocuments/Departments/CircuitClerk/AttorneyRes... (page title: RULES OF PRACTICE CIRCUIT COURT OF ILLINOIS TWENTIETH JUDICIAL COURT), which answered when SearchSystems opened it on October 11, 2026.
Illinois has no single public index of every trial court case; each court's records are looked up through that court.
The Illinois court page SearchSystems verified is at illinoiscourts.gov.
What Reaches the Court from St. Clair County
Together, the 17 agencies in St. Clair County with all twelve months of 2025 on file reported 6,114 arrests to the FBI that year; the State's Attorney decides which of those arrests become cases in the Circuit Court of St. Clair County.
The State's Attorney's page SearchSystems verified is at co.st-clair.il.us/departments/states-attorney (page title: State's Attorney | Departments | St. Clair), phone (618) 277-3892, 10 Public Square Belleville, IL 62220, which answered when SearchSystems opened it on September 23, 2026.
The Kinds of Court Files
The court file is one record with several readers: a criminal case from the arrest to the sentence, a divorce from the petition to the judgment, a traffic ticket from the citation to the conviction the court reports to the Illinois Secretary of State, and an eviction or a lien on land.
The other St. Clair County guides take the kinds of file one at a time: St. Clair County criminal records, St. Clair County divorce records, St. Clair County traffic tickets, St. Clair County DUI and St. Clair County property records.
More Official Court Pages for St. Clair County
The SearchSystems directory, online since 1997, lists the official pages for St. Clair County and Illinois. These court pages from its St. Clair County listing were opened again on October 2, 2026 and each one still answers:
- Courts, St. Clair County (co.st-clair.il.us)
Cities in St. Clair County
Wherever in the county a case arises, it is filed in 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:
- Belleville (40,560)
- O'Fallon (32,169)
- Cahokia Heights (17,052)
- Fairview Heights (16,115)
- Shiloh (14,754)
- Swansea (14,445)
Frequently Asked Questions
How do I look up a court case in St. Clair County?
The court records page SearchSystems verified for the county is at co.st-clair.il.us.
Which court hears felonies in St. Clair County?
The Circuit Court of St. Clair County, which hears every civil, criminal, family, probate, traffic and juvenile case.
Who keeps the court records in St. Clair County?
The Circuit Clerk. Copies come from that office under the court's own rules.
Is there a statewide court case search in Illinois?
No. Each court's records are looked up through that court.
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.