Reviewed and updated October 7, 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 on September 23, 2026.
Cook County, Illinois, has about 5.2 million residents (2024 Census Bureau estimate). A DUI arrest in Cook County starts two cases, a criminal case in the Circuit Court of Cook County and a license case before the Secretary of State, and leaves three records. This guide follows the arrest from the roadside to the court file and the driving record.
This guide covers the law, the arrest, booking, the court case, the license case, the records and common questions.
Related guides: Cook County public records, Cook County warrants, Cook County inmate search, Cook County criminal records, Cook County court records, Illinois arrest records and Illinois inmate search.
The DUI Law in Illinois
In Illinois the offense is DUI, and the limit is 0.08.
Driving in Illinois is consent to a breath or blood test when an officer has cause to suspect DUI; the license case that follows a refusal or a failed test is run by the Secretary of State, separately from the criminal case.
Illinois sets no time limit on prior offenses: every earlier conviction counts toward a repeat charge.
Who Makes DUI Arrests in Cook County
The Cook County Sheriff's Office and the agencies that report for Chicago, Cicero, Schaumburg, Evanston, Arlington Heights, Palatine and 112 more cities make the DUI arrests in Cook County.
The FBI's agency list also places these agencies in Cook County: the University of Illinois at Chicago, Chicago State University, Northeastern Illinois University, Oakton Community College and ten more (campus police); Canadian Pacific Railway, the Metra Police Department, the Chicago Heights Park District, Chicago Fire Department Arson Investigations and 11 more (other agency).
Together, the 100 agencies in Cook County with all twelve months of 2025 on file reported 71,187 arrests to the FBI that year, all offenses together; the FBI's count for Cook County does not break DUI out.
The Elgin Police Department, the Buffalo Grove Police Department, the Deerfield Police Department and eight more are each listed by the FBI across several counties including Cook County, so their arrests are not broken out for Cook County here.
Booking After a DUI Arrest in Cook County
A driver arrested for DUI and kept in custody goes to the county jail, whichever agency made the arrest. The jail, run by the Cook County Sheriff's Office, held about 4,790 people on an average day in 2024 by the Vera Institute of Justice's count and has a custody page SearchSystems verified at cookcountyil.gov/service/locate-inmate. The Cook County inmate search guide covers the jail in full.
The Court Case
The State's Attorney files the charge, and the case is heard in the Circuit Court of Cook County.
The State's Attorney's page SearchSystems verified is at cookcountyil.gov/agency/states-attorney, phone (312) 603-1880.
The court records page SearchSystems verified for the county is at cookcountyil.gov/service/court-records-and-archives.
Illinois has no single public index of every trial court case; each court's records are looked up through that court.
The License Case
A DUI arrest starts two cases: the criminal one above and an administrative one over the license, run by the Secretary of State. The driving record, kept by the Illinois Secretary of State, carries the result of both.
The Records a DUI Leaves
- The arrest report: from the agency that made the arrest, under the Illinois Freedom of Information Act.
- The court file: from the Circuit Court of Cook County, kept by the Circuit Clerk.
- The driving record: from the Illinois Secretary of State.
More on each: Cook County police reports and Cook County court records.
Frequently Asked Questions
What is the DUI limit in Illinois?
0.08 percent blood alcohol.
Where is a DUI case from Cook County heard?
In the Circuit Court of Cook County, brought by the State's Attorney. The court records page SearchSystems verified for the county is at cookcountyil.gov.
Where is a person arrested for DUI in Cook County held?
At the county jail, run by the Cook County Sheriff's Office, if kept in custody.
Who handles the license after a DUI arrest in Illinois?
The Secretary of State, in an administrative case separate from the court case.
How long does a DUI count as a prior in Illinois?
There is no time limit; every prior conviction counts.
Is this the official Cook 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.