Chicago Police Scanner: America's 3rd Largest City Goes Dark
Chicago has implemented one of the nation's most restrictive police radio policies—30-minute delays, active censorship, and complete encryption. Meanwhile, nearby Highland Park's open scanners helped save lives during a mass shooting. Here's the full picture of scanner access in the Chicago metro area.
Chicago Area at a Glance
Chicago represents one of the worst-case scenarios for public transparency. The Chicago Police Department, Chicago Fire, Cook County Sheriff, and CTA Transit Police have all gone fully encrypted—cutting off nearly 10 million metro area residents from real-time public safety information.
The contrast with nearby Highland Park is stark: when a mass shooter attacked the July 4th parade in 2022, Highland Park's open police scanners helped civilians avoid danger zones, locate loved ones, and make life-saving decisions in real time. Chicago's encrypted system would have left them in the dark.
The Highland Park Lesson: When Open Scanners Saved Lives
Highland Park (Open)
Lake County, IL - July 4, 2022
- Real-time scanner access during active shooter
- Civilians knew which areas to avoid
- Families located separated loved ones
- Journalists provided accurate, immediate updates
- Reduced 911 overload from information-seekers
- Result: Lives saved through public awareness
Chicago (Encrypted)
Cook County, IL - Same Region
- 30-minute delay on all communications
- Active censorship removes "sensitive" transmissions
- Zero real-time public awareness
- Media dependent on official statements only
- Social media rumors fill information vacuum
- Result: Public left in the dark during emergencies
Read the full Highland Park case study: How Scanners Saved Lives →
Chicago Metro Agency Status
| Agency | Type | Status | Notes |
|---|---|---|---|
| Chicago Police Department | Police | Encrypted | 30-minute delay, active censorship of transmissions |
| Chicago Fire Department | Fire | Encrypted | Encrypted alongside police communications |
| Cook County Sheriff's Office | Sheriff | Encrypted | County-wide encryption implemented |
| CTA Transit Police | Transit | Encrypted | Chicago Transit Authority fully encrypted |
| Illinois State Police District Chicago | State | Encrypted | STARCOM21 system, fully encrypted |
| DuPage County Sheriff | Sheriff | Partial | Some tactical channels encrypted; main dispatch varies by municipality |
| Lake County Sheriff | Sheriff | Partial | Mixed status; Highland Park PD remained open |
| Will County Sheriff | Sheriff | Partial | Partial encryption; some municipalities open |
| Kane County Sheriff | Sheriff | Partial | Mixed encryption status across municipalities |
| Metra Police | Transit | Encrypted | Commuter rail police fully encrypted |
How Chicago's Encrypted System Works
30-Minute Mandatory Delay
All scanner audio is held for at least 30 minutes before any public release. During active emergencies, this means the public hears nothing until long after events conclude.
Active Censorship
Police department staff review and remove transmissions before release. There's no public record of what's censored, no oversight, and no appeals process.
Broad Removal Criteria
Transmissions can be removed for "ongoing investigations," "sensitive information," "officer safety," or "victim privacy"—categories so broad that virtually anything qualifies.
Zero Real-Time Access
No journalists, residents, or emergency managers can hear live police communications. The public is completely dependent on official statements.
Beyond Chicago: Collar Counties & Suburbs
Cook County
Beyond Chicago proper, Cook County Sheriff and most suburban departments have followed Chicago's lead toward encryption. Over 5 million residents affected.
Lake County
Mixed status. Highland Park maintained open communications—a decision that proved critical during the 2022 mass shooting. Other municipalities vary.
DuPage County
Partial encryption. Some tactical channels encrypted while main dispatch varies by municipality. Check RadioReference for specific department status.
Will County
Mixed encryption status. Some municipalities remain accessible while others have followed the encryption trend. Joliet and other cities vary.
Kane County
Partial encryption across municipalities. Aurora and Elgin have varying policies. Check current status before assuming access.
McHenry County
Further from Chicago, McHenry County has historically maintained more open access, though this continues to evolve.
Listening to Remaining Open Agencies
While Chicago and Cook County are encrypted, some collar county agencies remain accessible. Here's how to monitor what's still available.
Online Streaming
Broadcastify hosts feeds for some collar county agencies. Search for specific counties (Lake, DuPage, Will, Kane) to find active feeds.
Find online feeds →Digital Scanner
Illinois agencies use various P25 systems. You'll need a P25 Phase II capable scanner for most modern systems. Encrypted agencies cannot be monitored.
Scanner buying guide →Check Before You Buy
Before investing in scanner equipment, verify your target agencies are actually open. RadioReference.com maintains current encryption status.
Illinois on RadioReference →Technical Details
- Chicago/Cook: STARCOM21 P25 Phase II - Fully Encrypted
- Collar Counties: Various P25 systems - Status varies by agency
- State Police: STARCOM21 - Encrypted statewide
- Resource: RadioReference Illinois Database
When Encryption Creates New Problems
January 2026: Chicago Officer Charged for Selling Radio Access
Chicago Police Officer Alain Dillon was charged with taking $500 payments to let others use his encrypted police radio—3 counts of bribery and 15 counts of official misconduct.
The irony: Encryption was sold as a security measure. Instead, it created a monetizable asset for corrupt officers. The public can't access police communications—but if you pay enough, apparently you can.
See 23+ documented cases of insider corruption →Fight Back: Restore Transparency in Illinois
Chicago's encryption represents a policy choice, not a technical necessity. Communities across Illinois can push back—and point to Highland Park as proof that open communications save lives.
Contact Your Alderman
Chicago's City Council has oversight over police policies. Demand answers about why encryption was implemented without evidence of harm from open scanners.
File FOIA Requests
Ask for documentation of any incidents where scanner access caused harm. Other cities have found zero responsive records—Chicago likely has none either.
Point to Highland Park
The July 4th shooting is undeniable proof that open scanners serve public safety. Make officials explain why Chicago chose the opposite approach.
Support Collar County Transparency
If you're in DuPage, Lake, Will, or Kane counties, engage now before encryption spreads. Thank agencies that remain open.
Frequently Asked Questions
Is Chicago Police Department radio encrypted?
Yes. The Chicago Police Department has fully encrypted their radio communications. Public access is limited to a 30-minute delayed feed with active censorship—transmissions deemed 'sensitive' are removed entirely before release. Real-time scanner access is completely blocked.
Can I listen to Chicago Fire Department on a scanner?
No. Chicago Fire Department communications are encrypted alongside police. Unlike many cities that keep fire and EMS open for public safety, Chicago has blocked access to all emergency service communications.
Is Cook County Sheriff encrypted?
Yes. The Cook County Sheriff's Office has implemented county-wide encryption. This affects the largest county in Illinois, covering over 5 million residents who have lost real-time access to public safety communications.
What about CTA Transit Police?
Fully encrypted. Chicago Transit Authority police communications cannot be monitored, meaning commuters have no real-time awareness of safety incidents on buses or trains.
Are the Chicago collar counties (DuPage, Lake, Will, Kane) encrypted?
Status varies by municipality. The collar counties have mixed encryption policies—some agencies remain open while others have encrypted. Notably, Highland Park in Lake County maintained open communications, which proved critical during the July 4, 2022 mass shooting.
Why did Chicago encrypt when Highland Park stayed open?
Chicago accelerated encryption after the 2020 protests when scanner access revealed officer misconduct and racist remarks. Highland Park maintained transparency, and during the 2022 July 4th shooting, open scanner access helped civilians avoid danger zones and locate loved ones—proving the public safety value of open communications.
What scanner do I need for Chicago area agencies?
For the few remaining open agencies in the collar counties, you'll need a P25 Phase II capable scanner. However, CPD, Chicago Fire, Cook County Sheriff, and most major agencies are encrypted and cannot be monitored regardless of equipment. Check RadioReference for current status of specific suburban departments.
Is there any way to listen to Chicago police?
The only legal option is the city's official 30-minute delayed feed, which is actively censored. There is no real-time public access. This represents one of the most restrictive scanner policies in the nation.