By Bob Paterson For motorists, no, using a laser jammer is not legal in Illinois. Illinois prohibits a person from operating or being in actual physical control of a motor vehicle equipped with a device designed to interfere with laser or radar frequencies used by police to measure vehicle speed. The restriction applies to ordinary passenger vehicles as well as commercial vehicles. However, Illinois law contains a limited exception for transporting an inactive jammer when it is properly secured or kept outside the passenger compartment.
What Does Illinois Law Say About a Laser Jammer?
The main Illinois law regulating laser jammers is 625 ILCS 5/12-613 of the Illinois Vehicle Code.
The statute prohibits a person from operating or being in actual physical control of a motor vehicle when the vehicle is equipped with an instrument designed to interfere with microwaves or lasers at frequencies used by police radar for monitoring vehicle speed.
This means a driver cannot legally install and operate a laser jammer to prevent or interfere with police speed-detection equipment.
The Illinois prohibition covers both radar jammers and laser jammers. It applies even though ordinary radar detectors remain legal for most drivers of private passenger vehicles.
What Is a Laser Jammer?
A laser jammer is an electronic device designed to interfere with police laser speed-measuring equipment, commonly known as LIDAR.
Police laser equipment sends light pulses toward a vehicle and calculates its speed based on the reflected signal. A laser jammer attempts to interfere with that process by transmitting signals that prevent or delay the equipment from obtaining an accurate speed reading.
This makes a jammer different from a detector.
A detector generally warns a driver that radar or laser signals are present. A jammer actively attempts to interfere with police equipment.
Illinois law treats those two types of devices differently.
Is a Radar Detector the Same as a Laser Jammer in Illinois?
No.
For an ordinary private passenger vehicle, a standard radar detector is generally legal in Illinois. Illinois specifically restricts radar detectors in qualifying commercial motor vehicles, but it does not impose the same general prohibition on private passenger cars.
A laser jammer is different because Section 12-613 applies broadly to motor vehicles.
Therefore, a person driving a private car may generally use a lawful radar detector but cannot legally operate the vehicle with equipment designed to jam police radar or laser speed-measuring signals.
Calling a device a “parking sensor” or another name would not necessarily make it legal if its actual design and function are to interfere with police speed-detection frequencies.
Can You Have a Laser Jammer in Your Car if It Is Turned Off?
Simply switching off an installed jammer may not always be enough.
Illinois provides a specific transportation exception. A driver does not violate Section 12-613 merely by possessing a radar or laser jamming device inside the vehicle when the device is:
- Not operating; and
- Contained in a locked opaque box or similar container; or
- Located outside the passenger compartment.
This exception is important because Illinois law distinguishes lawful transportation of an inactive device from having a vehicle equipped for illegal jamming.
A driver should therefore not assume that an installed jammer becomes lawful merely because the power switch has temporarily been turned off.
Is It Legal to Own a Laser Jammer at Home in Illinois?
Illinois Section 12-613 primarily regulates possession and use of a jammer in connection with operating or controlling a motor vehicle.
The statute does not establish a broad statewide prohibition making the mere possession of every laser-jamming device anywhere in Illinois a criminal offense.
For example, keeping such equipment outside a vehicle does not automatically fall within the motor-vehicle prohibition in Section 12-613.
However, installing or using the device in a vehicle in a manner prohibited by the statute creates the legal problem.
Federal communications rules may also apply to certain types of radio-frequency jamming equipment, particularly radar jammers.
Can You Use a Laser Jammer Only When Police Are Nearby?
No.
The Illinois offense does not depend on whether the jammer actually succeeds in defeating a police speed measurement.
A driver cannot avoid the law by activating the device only after seeing a police officer or receiving an alert that LIDAR is being used.
The relevant Illinois provision prohibits operating or controlling a motor vehicle equipped with the prohibited interference device.
Therefore, temporary or selective use does not create a legal exception.
Can Police Seize a Laser Jammer in Illinois?
Yes.
When a person violates Section 12-613, Illinois law provides that the radar or laser jamming device or mechanism shall be seized by the law-enforcement officer.
However, the statute does not automatically authorize permanent forfeiture of the device to the state.
The device can be held while it is needed as evidence. After it is no longer required for that purpose, the defendant may petition the court for its return.
To obtain the device back, the defendant must establish by a preponderance of the evidence that it will be used only for a legitimate and lawful purpose.
What Is the Penalty for Using a Laser Jammer in Illinois?
A violation of Illinois’s radar and laser jamming law is a petty offense.
The statute establishes a minimum fine of $50 for a first offense.
For a second or subsequent offense, the minimum fine increases to $100.
The jammer can also be seized by law enforcement as evidence.
Interestingly, Illinois law also states that a police officer may not stop or search a vehicle solely because of a violation or suspected violation of the jammer statute. This provision does not make the jammer legal; it simply limits enforcement actions based exclusively on suspicion of that particular violation.
Frequently Asked Questions
Q1. Can I legally use a laser jammer in my car in Illinois?
No. Illinois prohibits operating or being in actual physical control of a motor vehicle equipped with a device designed to interfere with police laser or radar speed-measuring frequencies.
Q2. Are radar detectors illegal in Illinois too?
Not generally in ordinary private passenger vehicles. Illinois treats radar detectors differently from jammers. Radar detectors are specifically prohibited in qualifying commercial motor vehicles, while laser and radar jammers are prohibited more broadly.
Q3. Can I transport a laser jammer through Illinois?
Yes, under limited conditions. The jammer must not be operating and must either be inside a locked opaque container or located outside the vehicle’s passenger compartment.
Q4. What happens if police find an illegal laser jammer?
A violation is a petty offense carrying a minimum $50 fine for a first offense and at least $100 for a subsequent offense. The device may also be seized and held as evidence.