In What States Are Radar Detectors Illegal? State-by-State Guide

In what states are radar detectors illegal? The legality of radar detectors is a topic of interest for many motorists in the United States. 

These devices, designed to alert drivers to the presence of police radar used to detect speeding, vary widely in their acceptance across different states. While some states permit their use in an effort to encourage safer driving speeds, others outright ban them to prevent drivers from evading law enforcement’s speed detection. 

So, in what states are radar detectors illegal, and where can you easily go about without violating any laws? Let’s find out.

In What States Are Radar Detectors Illegal?


What is a Radar Detector?

A radar detector is an electronic device used by motorists to determine if their speed is being monitored by law enforcement through a radar gun. These devices detect the radar waves emitted by radar guns and alert the driver, who can then reduce their speed before they are detected and potentially issued a speeding ticket.

Interesting Facts about Radar Detectors

Here are some interesting facts about radar detectors you might not know: 

  • Radar detectors were first introduced to the market in the 1960s.
  • Modern-day devices can detect multiple types of radar signals, including X, K, Ka, and Ku bands, each of which has a different wavelength and frequency.
  • Some radar detectors can also detect LIDAR (Light Detection and Ranging), a technology that some law enforcement agencies employ using light waves instead of radio waves to measure speed.
  • Despite their efficiency, radar detectors are not foolproof. Police can use techniques such as ‘instant-on’ radars, which only activate when the police officer triggers it, making it harder for the radar detector to provide timely warnings.
  • In spite of being legal in many places, radar detectors are outlawed in certain states in the U.S. and in countries like Australia and Brazil due to the concerns they encourage.

The Role of Radar Detectors

Radar detectors play a role in assisting drivers in monitoring their speed and alerting them when they are at risk of exceeding speed limits, especially in areas with active speed enforcement.

The idea is to allow drivers to slow down and comply with their area’s speed laws before they are caught and fined.

However, it is essential to note that the role of radar detectors is not to facilitate speeding or reckless driving. They should be used as a tool for promoting safe and responsible driving. Speed limits are there for a reason – to maintain safety on the roads. 

Remember, even with a radar detector, speeding is both dangerous and illegal and can lead to severe consequences.

How Do Radar Detectors Work? 

Radar detectors work on the principle of “Doppler Shift.” Law enforcement officers use radar guns that emit radio waves at specific frequencies. When these waves hit a moving object like a car, they bounce back with altered frequencies. 

By calculating the change in frequency, the radar gun can determine the object’s speed.

A radar detector is designed to pick up on these radar signals. The device is equipped with a radio receiver tuned to the frequencies commonly used by radar guns. When it receives a signal at those frequencies, it alerts the driver.

However, it is worth stating that not all signals detected by the radar detector will be from radar guns. Many automatic door openers, for instance, also emit radio waves at similar frequencies, which can result in false alerts.

What Are The Different Types of Radar Detectors? 

The different types of radar detectors you can find in the US market may include the following:

Corded Radar Detectors

These devices are most common, and typically mounted on the windshield with suction cups, providing the best detection range.

Cordless Radar Detectors

These detectors are portable in nature and can be easily moved between vehicles. They are also mounted on the windshield but don’t offer the same range as their corded counterparts.

Remote-Mount Radar Detectors

These devices are permanently mounted to the vehicle with a clean installation that’s virtually undetectable by thieves.

Radar Detector-Dashcam Combos

Some devices combine the functionality of a radar detector with a dashcam, helping drivers record their journeys while also monitoring for radar.

In addition, some modern-day radar detectors are also equipped with GPS technology to reduce false alarms by remembering false alert locations and adjusting sensitivity based on the vehicle’s speed. 

Some models can also connect to smartphone apps for real-time updates on speed traps from other users.

However, regardless of the type of radar detector, you must remember that the best policy is to always drive within the speed limit for the safety of others and yourself.

Are Radar Detectors Illegal In Any State?

Most states have policies encouraging the use of radar detectors as they can be helpful in managing on-road driving conditions. Using or possessing a radar detector in a vehicle is mostly legal. 

However, Mississippi and Virginia are notable exceptions to this rule. In these two states, the use or possession of a radar detector is unequivocally illegal, irrespective of the type of vehicle or location.

Those found guilty of contravening this law in either state could face misdemeanor charges and potentially incur fines reaching up to $250. Police also have the right to confiscate your device on the spot.

In What States Are Radar Detectors Illegal?

Mississippi and Virginia. 

However, there is some gray area in the Virginia law. You can possess a radon detector unless it is not accessible to any occupant in the vehicle and there’s no power source

The logic driving these prohibitions is to deter drivers from speeding and to bolster the enforcement of traffic regulations. The goal is to foster safer driving habits by preventing motorists from using radar detectors as a means to evade scrutiny from law enforcement authorities. 

Note: Federal law also prohibits using radar detectors on military bases.

Private Vehicles

In the states where radar detectors are legal, you can use them in your PRIVATE VEHICLE. However, laws can vary significantly, and here are some things you must know:


The legal framework regarding radar detectors in Iowa may appear complex at first glance. While it may seem that the law only prohibits “speed detector jamming devices,” it further extends to include radar speed meters, also called laser speed meters. Should your device interfere with, disrupt, or scramble a police radar gun, you could be subject to legal charges.

Minnesota and California

Both Minnesota and California permit the usage of radar detectors by private vehicle owners, albeit with certain restrictions. Expressly, they prohibit mounting these devices on windshields to prevent the obstruction of drivers’ views of the road. So, you must mount the device only on the dashboard.


Virginia imposes the most stringent regulations for radar detectors. It forbids their usage entirely within the state’s roadways, and their sale is also banned. Even though it is permissible to have a radar detector in the vehicle without a power source, the driver and passengers cannot access it in any form, rendering the device useless.

Other States

In the rest of the states, radar detectors are completely legal for use in private vehicles. However, it is important to be aware that particular radar detectors not only receive but also amplify the police radar signal, thereby affording drivers additional time to reduce their speed. These detectors function more like radar jammers, and different sets of laws may govern them.

Is It Legal to Use Radar Detectors in Commercial Vehicles?

The use of radar detectors in commercial vehicles is subject to specific restrictions. 

They are prohibited in all states in commercial vehicles exceeding a weight of 10,000 lbs. Commercial vehicles under 10,000 lbs. can use radar detectors, except in Illinois, Iowa, Minnesota, New Jersey, New York, Virginia, and Washington D.C.

In the case of interstate commerce, if you are driving a large rig such as an 18-wheeler, then even an inactive radar detector within the cab is strictly illegal. This prohibition, imposed by the Federal Highway Administration in 1994, is intended to deter speeding by these sizable trucks.

What About Radar Jammers?

Radar jammers, also known as scramblers, are not legal anywhere in the United States. They disrupt the broad signal law enforcement employs to monitor speeding vehicles and can even interfere with aviation. 

Federal law categorizes radar jammers as “malicious interference” under Section 333 of the Communication Act of 1934. Violations, even for first-time offenses, can lead to substantial fines and imprisonment.

And How About Laser Jammers?

The legality of laser jammers varies by state. They are banned in:

  • California
  • Colorado
  • Illinois
  • Iowa
  • Minnesota
  • Nebraska
  • Oklahoma
  • South Carolina
  • Tennessee
  • Texas
  • Utah
  • Virginia
  • Washington D.C.

However, they are admissible in other states due to the lack of a federal law prohibiting them.

Laser jammers function by sending back invisible light to the originating police LiDAR gun, causing major confusion. These laser guns provide a more focused approach, enabling officers to single out a specific vehicle more efficiently. The returned signal disrupts the laser gun, preventing the officer from accurately determining the driver’s speed.

State-Wise Legalities of Radar Detectors

Now that you know the answer to “In What States Are Radar Detectors Illegal,” let us tell you about the states where you can legally use your radar detector without any worries:

  1. Alabama
  2. Alaska
  3. Arizona
  4. Arkansas
  5. California
  6. Colorado
  7. Connecticut
  8. Delaware
  9. Florida
  10. Georgia
  11. Hawaii
  12. Idaho
  13. Illinois
  14. Indiana
  15. Iowa
  16. Kansas
  17. Kentucky
  18. Louisiana
  19. Maine
  20. Maryland
  21. Massachusetts
  22. Michigan
  23. Minnesota
  24. Missouri
  25. Montana
  26. Nebraska
  27. Nevada
  28. New Hampshire
  29. New Jersey
  30. New Mexico
  31. New York
  32. North Carolina
  33. North Dakota
  34. Ohio
  35. Oklahoma
  36. Oregon
  37. Pennsylvania
  38. Rhode Island
  39. South Carolina
  40. South Dakota
  41. Tennessee
  42. Texas
  43. Utah
  44. Vermont
  45. Washington
  46. West Virginia
  47. Wisconsin
  48. Wyoming

The Final Say

Understanding the laws surrounding radar detectors is essential for all drivers across the United States. While they are generally legal, some states like Virginia and Mississippi enforce strict restrictions against them, and there are specific regulations for commercial vehicles as well. 

Furthermore, the use of laser jammers and radar jammers is heavily regulated and can be outright illegal in many states. These limitations aim to promote safer driving habits and prevent motorists from depending on these devices to evade law enforcement.

As a responsible driver, it is crucial to respect these laws to not only avoid legal consequences but to ensure the safety of all road users. 

So, always stay updated on local regulations and prioritize safety over speed.