Wisconsin Police Codes: The Complete 2026 Scanner Reference Guide
This guide addresses the public safety radio codes, ten-codes, and signal codes utilized by Wisconsin law enforcement and emergency dispatchers; it is distinct from the Wisconsin State Legislature's statutory criminal codes.
Deciphering the rapid-fire radio transmissions of Wisconsin law enforcement requires a clear understanding of specialized communications. Despite a national push toward plain-language radio transmissions, public safety agencies across the Badger State—including the Wisconsin State Patrol, county sheriff departments, and municipal police forces—rely heavily on legacy "ten-codes" and regional signal codes.
In 2026, as radio systems transition increasingly to encrypted digital platforms, knowing these codes is essential for scanner enthusiasts, journalists, emergency management personnel, and mutual aid partners. This guide provides an authoritative, technically precise breakdown of Wisconsin police codes, regional variations, and the technical landscape of modern public safety communications.
The Wisconsin State Patrol Standard Ten-Codes
The Wisconsin State Patrol (WSP) establishes the baseline for public safety communications across the state. While local jurisdictions may introduce slight variations, the WSP ten-code list is the most widely recognized standard. These codes allow state troopers and dispatchers to communicate complex status updates, requests for assistance, and situational hazards quickly and with minimal radio traffic.
| Ten-Code | Standard Meaning (Wisconsin State Patrol) | Operational Status / Action Required |
|---|---|---|
| 10-1 | Receiving Poorly / Weak Signal | Adjust antenna, change location, or switch repeaters. |
| 10-2 | Receiving Well / Clear Signal | Signal strength is optimal for transmission. |
| 10-3 | Stop Transmitting | Clear the channel immediately for emergency traffic. |
| 10-4 | Acknowledged / OK | Message received, understood, and will comply. |
| 10-5 | Relay | Pass information from one unit/agency to another. |
| 10-6 | Busy, Stand By | Officer or dispatcher is occupied; wait to transmit. |
| 10-7 | Out of Service | Unit is unavailable for dispatch (e.g., shift ended). |
| 10-8 | In Service | Unit is active, patrolling, and available for calls. |
| 10-9 | Repeat Transmission | Requesting the sender to repeat the last message. |
| 10-10 | Fight in Progress | Immediate dispatch of backup required; physical altercation. |
| 10-12 | Stand By / Visitors Present | Unauthorized personnel are near the radio receiver. |
| 10-13 | Advise Weather/Road Conditions | Requesting meteorological or highway status. |
| 10-14 | Prowler Report | Suspicious person lurking around a property. |
| 10-15 | Subject in Custody | Suspect has been arrested and secured in the vehicle. |
| 10-19 | Return to Station | Report back to the designated precinct or headquarters. |
| 10-20 | What is Your Location? | Report current geographic coordinates or intersection. |
| 10-21 | Call by Telephone | Contact dispatcher or specific unit via phone line. |
| 10-22 | Cancel Last Assignment | Disregard the previous dispatch directive. |
| 10-23 | Arrived at Scene | Unit is on-site at the designated dispatch location. |
| 10-25 | Meet in Person | Requesting a face-to-face meeting with another unit. |
| 10-27 | Driver's License Check | Querying DMV databases for operator status and history. |
| 10-28 | Vehicle Registration Check | Querying license plate for owner and registration validity. |
| 10-29 | Check for Warrants / Stolen Status | Run name or VIN through NCIC and CIB databases. |
| 10-33 | Emergency Radio Traffic | Only life-safety transmissions permitted on this frequency. |
| 10-41 | Beginning Tour of Duty | Log on to the active dispatch system for the shift. |
| 10-42 | Ending Tour of Duty | Log off the active dispatch system; end of shift. |
| 10-43 | Chase in Progress | Active pursuit of a non-compliant fleeing vehicle. |
| 10-45 | Fuel and/or Maintenance | Unit is out of service temporarily for vehicle service. |
| 10-50 | Motor Vehicle Crash | Accident reported (often clarified with "Injury" or "PD" for Property Damage). |
| 10-51 | Tow Truck Needed | Requesting a wrecker to clear a disabled or impounded vehicle. |
| 10-52 | Ambulance Needed | Immediate dispatch of emergency medical services (EMS). |
| 10-70 | Fire Alarm | Report of active structure, wildland, or vehicle fire. |
| 10-78 | Officer Needs Assistance | Urgent request for backup due to escalating danger. |
| 10-80 | Pursuit in Progress | Active tactical pursuit of a suspect or vehicle. |
| 10-96 | Mental Health Subject | Situation involving an individual experiencing a psychological crisis. |
| 10-97 | Arrived at Scene (Alternate) | Used by specific regional dispatchers to confirm on-scene status. |
Regional Variations: County and Municipal Dispatch Systems
Wisconsin's decentralized system of 72 counties means that local emergency communications centers (ECCs) often diverge from the state standard. While a 10-4 is universally understood as "acknowledgment," other codes shift dramatically based on geography.
Southeast Wisconsin: Milwaukee and Waukesha Counties
In densely populated Milwaukee County, the Sheriff’s Office (MCSO) and the Milwaukee Police Department utilize highly streamlined communication formats. Due to heavy call volumes, dispatchers prioritize brevity.
In these urban environments, codes like 10-10 (Fight) are regularly sub-categorized by weapon types (e.g., "10-10 with a cutting instrument" or "10-10 with a firearm"). Furthermore, Waukesha County dispatch utilizes a combined APCO-based system that integrates plain language alongside standardized ten-codes to coordinate responses between municipal police departments and county deputies.
Madison and Dane County
Dane County's 911 Communications Center serves as a primary hub for municipal, county, and state university public safety units. Dane County historically led the state in transitioning toward "Plain Language" for inter-agency operations. However, legacy ten-codes are still heavily utilized during localized, single-agency dispatch loops.
For instance, Dane County dispatchers frequently utilize 10-25 to coordinate secure meetings between municipal officers and county deputies when handling multi-jurisdictional transport duties.
Northern Wisconsin: Rural and Tribal Law Enforcement
In northern counties such as Oneida, Vilas, and Ashland, where geography is vast and backup can be miles away, radio codes prioritize absolute safety and clarity. The code 10-78 (Officer Needs Assistance) is treated with the utmost gravity in these areas, triggering automatic mutual-aid dispatches across county lines and integrating tribal law enforcement agencies, such as the Great Lakes Indian Fish & Wildlife Commission (GLIFWC) wardens.
Wisconsin State Fair Park Police Department — Cardinal Police Diecast
Technical Infrastructure: Digital Trunking and WISCOM
To fully comprehend how these codes are transmitted, it is necessary to understand Wisconsin's public safety communications infrastructure.
The WISCOM P25 System
In 2026, the Wisconsin Interoperable System for Communications (WISCOM) serves as the primary backbone for statewide public safety radio traffic. WISCOM is an 800 MHz Project 25 (P25) digital trunked radio system designed to allow local, county, state, and federal agencies to communicate seamlessly during large-scale emergencies.
- P25 Phase II Digital Audio: Unlike old analog systems, P25 digital systems compress voice data, delivering clear audio up to the very edge of a tower's coverage area.
- Talkgroups: Instead of traditional "channels," digital trunking systems use virtual "Talkgroups." Dispatchers and officers can be dynamically assigned to specific talkgroups based on the incident type.
- Interoperability: WSP can patch into local county talkgroups, allowing state troopers to coordinate directly with local deputies using shared ten-codes and plain language.
Encryption Challenges in 2026
A major consideration for scanner enthusiasts is the steady march toward radio encryption. Under federal CJIS (Criminal Justice Information Services) data-security guidelines, agencies are increasingly encrypting their primary dispatch and tactical channels to protect personally identifiable information (PII) transmitted over the air during 10-27 and 10-28 queries.
In many Wisconsin jurisdictions, routine dispatch remains unencrypted (clear), while tactical, drug task force, and special operations channels are fully encrypted.
The Pros and Cons of Radio Codes vs. Plain Language
The ongoing debate between using structured codes and migrating entirely to plain language is highly relevant to Wisconsin's public safety agencies.
Structured Radio Codes (Ten-Codes & Signals)
Pros
- Breathing Room on the Airwaves: Codes condense long sentences into a few syllables, keeping airtime clear for other urgent calls.
- Operational Privacy: Passersby or suspects cannot easily understand what the officer is planning (e.g., calling for a 10-29 warrant check).
- Emotional Neutrality: Saying "10-52" or "10-70" keeps the radio traffic calm, preventing panic during intense emergencies.
Cons
- Interoperability Issues: A code used by a local police department might mean something completely different to a state trooper or an out-of-state mutual aid unit.
- Training Burden: New dispatchers and officers must memorize hundreds of codes, increasing the onboarding timeline.
Plain Language (NIMS/FEMA Standard)
Pros
- Universal Clarity: Anyone from any agency can immediately understand what is being communicated without a cheat sheet.
- Reduced Errors: Lowers the risk of a misheard code during high-stress, multi-agency disaster responses.
Cons
- Airwave Congestion: Describing a situation in full sentences takes significantly longer, potentially blocking critical emergency transmissions.
- Zero Privacy: Anyone listening to an unencrypted scanner can immediately comprehend sensitive operational details in real-time.
Practical Guide to Monitoring Wisconsin Police Scanners
Listening to police scanner traffic remains a popular hobby and a valuable tool for localized situational awareness. However, doing so in Wisconsin requires appropriate hardware and compliance with local laws.
Step 1: Secure the Correct Hardware
Because Wisconsin relies heavily on the WISCOM P25 Phase II digital network, a basic analog scanner will not capture most law enforcement traffic. You must use a digital trunking scanner capable of decoding P25 Phase II signals, such as the Uniden SDS100, Uniden SDS200, or Whistler TRX-1.
Step 2: Program Local Talkgroups
Using software like Sentinel or ARC, program the specific Control Channels for the WISCOM towers nearest to your location. Then, import the talkgroup IDs (TGIDs) for your local county sheriff, municipal police, and Wisconsin State Patrol regional posts.
Step 3: Understand the Audio Flow
When monitoring, you will typically hear a sequence like this:
Dispatch: "Unit 402, copy a 10-50 property damage at Highway 12 and County Road K."Unit 402: "402, copy. Step me a tow, 10-51."Dispatch: "Copy, 402. Tow is en route. Check 10-29 on Wisconsin registration Alpha-Bravo-Charlie-1-2-3."
In this exchange, the dispatcher assigns a property damage accident (10-50), the officer requests a tow truck (10-51), and the dispatcher confirms a tow is coming while requesting a warrant check (10-29) on the vehicle's plate.
Legal Considerations in Wisconsin
Under Wisconsin State Statute, it is generally legal to own and operate a radio scanner in your home or vehicle for personal use. However, there are two critical legal boundaries:
- Commission of a Crime: Using a police scanner to assist in committing, facilitating, or escaping from a crime elevates the charges and is classified as a distinct criminal offense.
- Commercial Interception: Utilizing intercepted public safety communications for direct commercial gain or to interfere with emergency personnel is strictly illegal.
Frequently Asked Questions About Wisconsin Police Codes
What does 10-4 mean in Wisconsin?
Direct Answer: In Wisconsin, 10-4 is the universal public safety radio code for "Acknowledged" or "OK."
It indicates that the receiving party has heard, understood, and will comply with the transmission. It does not necessarily mean "yes" to a question, but rather serves as a confirmation of clear receipt of information.
Why do some Wisconsin counties use different codes than the State Patrol?
Direct Answer: Wisconsin operates on a decentralized dispatch model where individual counties and municipalities maintain historical autonomy over their localized communication systems.
Over many decades, local sheriffs developed customized signal codes tailored to their unique geographic challenges and staffing needs. While the WISCOM network has standardized inter-agency talkgroups, local dispatch loops still utilize these legacy local codes for day-to-day operations.
What is a "10-43" in Wisconsin law enforcement?
Direct Answer: A 10-43 refers to an active vehicle pursuit or chase in progress.
When an officer calls out a "10-43," dispatch immediately clears the channel of routine traffic, shifts secondary units to tactical frequencies, and begins coordinating tire deflation devices or PIT maneuvers.
Can I listen to encrypted Wisconsin police channels?
Direct Answer: No, it is impossible for civilian scanners to monitor encrypted public safety transmissions.
Decryption keys are highly secure and managed directly by the Wisconsin Department of Military Affairs and local radio administrators. Only authorized agency radios programmed with the correct cryptographic keys can decode these transmissions.
What does "10-96" mean on a Wisconsin scanner?
Direct Answer: A 10-96 code denotes a call involving an individual experiencing a mental health crisis or psychological instability.
This code alerts responding officers to utilize crisis intervention team (CIT) de-escalation protocols and to coordinate with county mental health professionals if necessary.
Elevating Your Situational Awareness
Understanding Wisconsin's police codes is more than just memorizing numbers; it is about grasping the operational flow of public safety professionals who work to keep Wisconsin's communities safe. Whether you are programming a digital trunking scanner for the first time, keeping tabs on local traffic incidents, or coordinating inter-agency emergency responses, recognizing these codes provides clear, immediate insight into active incidents. Keep a copy of this 2026 reference guide handy, and always prioritize safety and legality when monitoring public safety communications.
