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 2, 2026.
DeKalb County, Illinois, has about 101,000 residents (2024 Census Bureau estimate). A DUI arrest in DeKalb County starts two cases, a criminal case in the Circuit Court of DeKalb 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: DeKalb County public records, DeKalb County arrest records, DeKalb County warrants, DeKalb County inmate search, DeKalb County criminal 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 DeKalb County
The DeKalb County Sheriff's Office and the agencies that report for DeKalb, Sycamore, Sandwich, Genoa, Cortland, Hinckley and four more cities make the DUI arrests in DeKalb County.
The FBI's agency list also places one more agency in DeKalb County: Northern Illinois University (campus police).
Together, the nine agencies in DeKalb County with all twelve months of 2025 on file reported 2,362 arrests to the FBI that year, all offenses together; the FBI's count for DeKalb County does not break DUI out.
The Maple Park Police Department is listed by the FBI across two counties including DeKalb County, so its arrests are not broken out for DeKalb County here.
Booking After a DUI Arrest in DeKalb 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 DeKalb County Sheriff's Office, held about 120 people on an average day in 2023 by the Vera Institute of Justice's count and has a custody page SearchSystems verified at dekalbsheriff.com. The DeKalb 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 DeKalb County.
The State's Attorney's page SearchSystems verified is at dekalbcounty.org, phone 815-895-7164.
The court records page SearchSystems verified for the county is at dekalbgastatecourt.gov.
Illinois has no single public index of every trial court case; each court's records are looked up through that court.
The License Case
The court case is only half the record. The Secretary of State runs a separate administrative case over the license, which can suspend it before the criminal case is decided, and the Illinois Secretary of State keeps the driving record the conviction goes on.
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 DeKalb County, kept by the Circuit Clerk.
- The driving record: from the Illinois Secretary of State.
More on each: DeKalb County arrest records, DeKalb County police reports and DeKalb County court records.
Frequently Asked Questions
What is the DUI limit in Illinois?
0.08 percent blood alcohol.
Where is a DUI case from DeKalb County heard?
In the Circuit Court of DeKalb County, brought by the State's Attorney. The court records page SearchSystems verified for the county is at dekalbgastatecourt.gov.
Where is a person arrested for DUI in DeKalb County held?
At the county jail, run by the DeKalb 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 DeKalb 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.