Reviewed and updated October 7, 2026 by the SearchSystems.net editorial team. 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 September 25, 2026.
Chicago, Illinois, in Cook County, has about 2.7 million residents (2024 Census Bureau estimate), and its arrests are reported to the FBI by an agency of its own. An arrest in the city leaves the same records whoever makes it: the arresting agency's report, the booking at the county jail, and, if the State's Attorney files charges, a case in the Circuit Court of Cook County. This guide says who keeps each one, what it costs and who may see it.
This guide covers who makes arrests, booking and the jail, finding an arrest, copies and common questions.
Related guides: Chicago public records, Cook County public records, Illinois arrest records and Illinois inmate search.
Who Makes Arrests in Chicago
The FBI lists Chicago with an arrest reporting agency of its own, filed as Chicago Police Department. A city is listed separately whether the officers are the city's own or the sheriff's under contract; the FBI's list does not say which.
Outside the city, the Cook County Sheriff's Office is the county agency.
The FBI's agency list also places these agencies in Cook County: University of Illinois: Chicago, Chicago State University, Northeastern Illinois University and Oakton Community College and ten more (campus police); Canadian Pacific Railway, Metra Police Department, Chicago Heights Park District and Chicago Fire Department Arson Investigations and 11 more (other).
Booking: Where People Arrested in Chicago Are Held
Whoever makes the arrest in Chicago, the booking is at the county jail. The jail's record of each person held, with the charges, is the first public record of an arrest, and the court file takes over from there.
On an average day in 2024 the jail held about 4,790 people, down from about 5,770 in 2019. Its rated capacity in 2023, the last year with a capacity figure, was 7,084 beds, and it ran at 73 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 Cook County Sheriff's Office at cookcountyil.gov/service/locate-inmate (page title: Locate an Inmate), which answered when SearchSystems opened it on September 23, 2026.
A sentence of more than a year is served in state prison; the Illinois Department of Corrections lists its inmates at idoc.illinois.gov/offender/inmatesearch.html.
How to Find Out About an Arrest in Chicago
Whether someone was arrested in Chicago, and what came of it, shows up in two places: the case index of the Circuit Court of Cook County, which shows whether charges were filed and the next court date (the court records page SearchSystems verified is at cookcountyil.gov/service/court-records-and-archives); the State's Attorney, which decides whether an arrest becomes a charge (its page is at cookcountyil.gov/agency/states-attorney, phone (312) 603-1880).
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 Chicago
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 Chicago police: the police records page SearchSystems verified at chicago.gov/city/en/depts/cpd/supp_info/cpd_foia.html (page title: City of Chicago | File a Police FOIA Request), which answered when SearchSystems opened it on September 25, 2026.
- An arrest by the Cook County Sheriff's Office: ask its records unit.
- A defendant who has been charged gets the report through the case: the State's Attorney, (312) 603-1880, handles discovery for pending cases.
- The court file of a case that was filed: the Circuit Court of Cook County, through its records page at cookcountyil.gov.
- Your own statewide record: a name-based or fingerprint-based request to the Illinois State Police.
Frequently Asked Questions
How do I find out if someone is in jail in Chicago?
Ask the Cook County Sheriff's Office; its jail page SearchSystems verified is at cookcountyil.gov/service/locate-inmate.
Where are people arrested in Chicago booked?
In the county jail, run by the Cook County Sheriff's Office.
Are arrest records public in Chicago?
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 Chicago?
From the agency that made the arrest: the Chicago police for its own arrests, the Cook County Sheriff's Office for the sheriff's. Under the Illinois Freedom of Information Act the answer is due within 5 business days, with one 5-day extension.
Is this the official Chicago website?
No. SearchSystems.net is an independent public records guide, online since 1997. It links to the official city, county, court and state offices described above and does not hold records, charge for them or take requests.