Police Scanner Encryption Explained


Encryption means no scanner can monitor.

There are 2 types of encryption:

  1. PARTIAL encryption
    1. Example: SWAT team, FBI, etc.
    2. Use: Most areas have partial encryption
  2. FULL encryption
    1. Example: 100% of Pennsylvania State Police are encrypted
    2. Use: Very few areas in the US have full encryption


If your area is fully encrypted - no scanner can monitor. There are no loopholes or tricks to get around full encryption.


If your area has partial encryption you can still monitor quite a bit, just not what is encrypted.


To find out, exactly, what you can and cannot monitor in your area skip to Ultimate Encryption Guide


Watch our Police Scanner Encryption Tutorial to learn more.


Quick Jump

Chapter 1:

Encryption History


Privatizing radio communications, both partially and fully, has become uncomfortably common since the transition away from long-held analog radio systems.


In the early 2000s, the advent of digital trunking systems spurred further concern that citizens would utilize scanners whilst committing a crime to evade law enforcement.


People with favorable opinions on encryption believe that arming criminals with portable radios to monitor police activity is detrimental to officer safety.


People who oppose encryption believe that, when the public (including news sources) is denied access to police information, it leads to an inability for officers to be held accountable.


This directly and indirectly affects U.S citizens, especially those who use police scanner radios to monitor transmissions including the media, amateur radio hobbyists, citizens, and anyone who uses a scanner to hear what’s going on in their area in real time.


Encryption of public airwaves by the government is a highly debated issue in the US and most states have some form of non-tactical encryption.


What is encrypted varies from state to state (and often county to county) all over the US.


Each county (and to a lesser extent, municipality) makes its own laws regarding the deployment of encryption.


Chapter 2:

Types of Encryption

Encryption can be grouped into 2 different categories:

Tactical Encryption

Every state has some form of tactical encryption. Where there is a private investigation, there is privatized communication.

Tactical situations are assumed encrypted, such as police channels that involve:

  • Drug enforcement
  • Gang enforcement
  • Hostage negotiation
  • Stakeout
  • FBI
  • CIA
  • SWAT

Full Encryption

Some areas block all radio communication from unauthorized civilians. This often includes:

  • Police Dispatch
  • Police Tac
  • Car-to-Car
  • Event
  • Talk
  • Info

Fire and EMS are encrypted far less frequently, but there are areas where all emergency response communication is encrypted regardless of the agency.

Chapter 3:

Areas Affected by Encryption

 *Encryption percentage is rounded to the nearest 10

Metro Area Encryption* % Simulcast DMR NXDN ProVoice
New York City 20% X X X
Los Angeles 20% X X X
Chicago 10% X X X
Houston 20% X X
Phoenix 30% X X X
Philadelphia 40% X X X
San Antonio 0% X X
San Diego 10% X X X
Dallas 0% X
San Jose 80% X X X X
Austin 10% X X X
Jacksonville 100% X X X
Fort Worth 90% X X X X
Columbus 0% X X X
Charlotte 0% X X X
San Francisco 20% X X X X
Indianapolis 0% X X X X
Seattle 0% X X X
Denver 100% X X X
Washington, D.C. 70% X X X
Boston 0% X X X X
El Paso 10% X X X
Nashville 90% X X X
Detroit 40% X X X
Oklahoma City 60% X X X
Portland 40% X X X
Las Vegas 0% X X X
Memphis 10% X X X
Louisville 40% X X X
Baltimore 0% X X X
Milwaukee 30% X X X
Alberquerque 50% X X X
Tucson 0% X X X
Fresno 0% X X X X
Mesa 30% X X X
Sacramento 10% X X X
Atlanta 10% X X X
Kansas City 10% X X X X
Colorado Springs 20% X X X
Omaha 10% X X X X
Raleigh 20% X X X
Miami 40% X X X X
Long Beach 10% X X X
Virginia Beach 20% X X X X
Oakland 10% X X X
Minneapolis 10% X X X
Tulsa 70% X X X X
Tampa 20% X X X
Arlington 10% X X X X
New Orleans 90% X X X X

Encryption isn’t always permanent, but once it reaches the state and federal level, it typically sticks.


Accurate, up-to-date information on encryption is difficult to keep track of because they change and, just for funsies, revert back.


Exhausting, right? We can look this up for you!


Want to research on your own? You can use the same database the pros use: RadioReference.


RadioReference has the most accurate frequency database—you can look at your area here.


RadioReference is a user-generated database (like Wikipedia), so any updates will take time to appear.


Below is an example of basic law enforcement encryption illustrated on RadioReference.

Sheriff Encryption

Note: DE, TE, or De under Mode on RadioReference signifies encryption


The prime example of an encryption decision not sticking is the Orange County Fire Department, who decided to reverse encryption in October 2019.


As of January 2021, fire communication has still not been decrypted. Decrypting channels isn’t a flip of the switch, techs have to decode these channels one by one.


Below is the system Orange County Fire operates on and what it looks like on Radio Reference.


Here are the channels that are supposed to get decrypted


For an example of encryption that likely isn't going away, there are two states with full encryption on statewide police:


Florida State Police


Pennsylvania State Police

Chapter 4:

Arguments For & Against Encryption of Police Communication

Reasons to Keep Police Communication Open

  • 1st Amendment (key phrase: “petition the Government for a redress of grievances”)
  • Government transparency
  • Citizen & media monitoring
  • To allow citizens & off-duty public safety personnel to respond to emergencies
  • Backup & neighboring police officers receive delayed information
  • Inhibits the media’s ability to accurately report news in real time & inform citizens
  • Open communication with a three-minute delay would suffice
  • Police utilize cell phones for conversations they don’t want to put over the radios
  • Is encryption secure enough to keep crafty criminals at bay?

Reasons to Encrypt Police Communication

  • Safety of law enforcement
  • Criminals monitor communication to evade police
  • Officers have arrested suspects in the possession of handheld radios
Chapter 5:

The Future of Radio Communication


Is encryption the end of scanning?

  • Not quite. Even in areas where there is full digital encryption such as Washington D.C. there are still plenty of analog channels to listen to including non-encrypted police backup channels, fire, EMS, businesses, aviation, NASCAR, NOAA & more.
  • Railroad frequencies have remained the same for decades.
  • Some encryption decisions have been reversed after years of encryption.
  • The citizens’ fight against encryption won’t end anytime soon.

Is there a mutually beneficial compromise to combat radio silence?

  • In some ways partial encryption is a small consolation, but it’s no substitute for open communication
  • Some departments have utilized a 15-minute delay (narrowing that time frame)
  • Keep standard police calls open and encrypt tactical situations
  • Encryption decisions should be left up to municipal officials, not the county
  • Give volunteer emergency response representatives and neighborhood watch coordinators access to police communication to spark a head start
Chapter 6:

Encryption FAQ


Can I monitor encrypted signals?

  • No. This is illegal & no police scanner (that the public can access) can monitor encrypted channels.

Where can I read more about encryption?

There are countless local articles & local news segments regarding police encryption, but here are some of the best articles that address the issues surrounding police encryption:

Encryption is being debated in my area. What can I do to stop it?

  • Contact your legislator
  • Start an opposition group
  • Start a petition