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. 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 11, 2026.
Peru, Illinois, in LaSalle County, has about 9,800 residents (2024 Census Bureau estimate). A DUI arrest in Peru starts two cases, a criminal case in the Circuit Court of LaSalle 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: Peru public records, LaSalle County DUI, Peru arrest records, Peru warrants, Peru inmate search, Peru 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 Peru
The La Salle County Sheriff's Office and the agency that reports for Peru (filed by the FBI as Peru Police Department) make the DUI arrests in and around Peru.
The FBI's agency list also places one more agency in LaSalle County: Tri-County Drug Enforcement Narcotics Team (other agency).
Together, the 13 agencies in LaSalle County with all twelve months of 2025 on file reported 2,788 arrests to the FBI that year, all offenses together; the FBI's count for LaSalle County does not break DUI out.
The Somonauk Police Department is listed by the FBI across two counties including LaSalle County, so its arrests are not broken out for LaSalle County here.
Booking After a DUI Arrest in Peru
A driver arrested for DUI and kept in custody goes to the county jail, whichever agency made the arrest. The jail, run by the La Salle County Sheriff's Office, held about 110 people on an average day in 2019 by the Vera Institute of Justice's count and has a custody page SearchSystems verified at lasalleso.com/inmateSearch. The Peru 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 LaSalle County.
The State's Attorney's page SearchSystems verified is at lasallecountyil.gov, phone 815-434-8340.
The court records page SearchSystems verified for the county is at lasallecounty.com/i-want-to/request/court-transcripts, phone 815-434-0786.
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 LaSalle County, kept by the Circuit Clerk.
- The driving record: from the Illinois Secretary of State.
More on each: Peru arrest records and Peru court records.
Frequently Asked Questions
What is the DUI limit in Illinois?
0.08 percent blood alcohol.
Where is a DUI case from Peru heard?
In the Circuit Court of LaSalle County, brought by the State's Attorney. The court records page SearchSystems verified for the county is at lasallecounty.com.
Where is a person arrested for DUI in Peru held?
At the county jail, run by the La Salle 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 Peru 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.