Radar Detector Rules For All 50 States

What are radar detectors?

Before we go through the radar detector rules, you need to know what a radar detector is. In simple terms, it is a device which is mounted on the windscreen of the car to alert you if a police radar gun is scanning your speed. A radar detector, therefore, is the surest way of avoiding a speeding ticket.

Are radar detectors legal?

Use of radar detectors is prohibited in some states. A driver who uses these devices is more likely to cause an accident than the one who does not. Another reason why they are illegal is that they cause a distraction to drivers since they may spend most of the time checking whether their speed is being monitored.

If you are in the United States, you will learn some of the radar detector rules in various states from this article but before then, let me explain how radar detectors work. To read more about radar rules, see this review at 10BestRanked.

How does a radar detector work?

To start with, you need to know how radars work. Radars are usually used to check the speed and distance or just how far away a car is or the speed in which it is moving. Radar devices produce radio waves which run at a very high speed.

When they meet an object, the waves roll back to the device. The distance between the device and the object can be determined by the time it takes for the radio waves to reach to the designated object and the speed at which they move back to the device.

When a radar device is used to check the speed of a car, the radio wave frequency of the bounced signal is affected because the vehicle is in motion. Therefore, radar detectors act as radio receivers.

They single out specific frequencies which are used by the police radar guns. This means that they can detect the police radar guns before the vehicle comes close to the police radar guns.

You should note that there are some advanced radar detectors which apart from detecting the police radar, they are also able to distort their reading. These devices usually use a radio transmitter which produces a scrambled signal.

Radar Detector Rules In Different States

Before buying a radar detector for your car, you need to know the rules of using these devices in your area or the state you will be driving in. Another thing you should know is that these rules vary from one state to another. The consequences of using these devices could be worse than when you are caught speeding.


Radar detector rules in Virginia bans the use of radar detectors in all vehicles. If you are caught, you will be given a ticket and your car will be confiscated. This law is valid even if you are not speeding. The law also does not allow selling radar detectors in Virginia.

Minnesota and California

Radar detectors can be used in California and Minnesota. However, you are not allowed to mount them on the inside of the car’s windscreen.

Illinois (IL), New York (NY) and New Jersey (NJ)

In these states, you can only use radar detectors in private cars. They cannot be used in commercial vehicles.

All other states

Radar detectors are allowed in all other states even without windscreen mounting issues or commercial vehicle restrictions.

It is also good to know that there are federal laws which prohibit the use of radar detectors in all commercial vehicles which exceed 10,000 pounds. This means irrespective of your state, you cannot use a radar detector in cars which is under this category.

Final words

Finally, even if you are using a radar detector, it is good to ensure that you are driving at a safe speed to avoid accidents. Use of radar detectors will help you to avoid tickets and insurance costs. All you need to do is to be conversant with radar detector rules in your state.


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