Are Radar Detectors Legal? Where They're Banned, State Rules, Trucks and Mounts

by Farrukh Shahzad · Updated

Radar detector mounted inside a car
Contents
  1. How radar detectors work, and why some places ban them
  2. Where are radar detectors illegal?
  3. Are radar detectors legal in Georgia?
  4. Are radar detectors legal in Michigan?
  5. Commercial trucks and buses: the federal ban
  6. Windshield mounting rules
  7. Before you buy or travel
  8. State guides
  9. Sources

Last reviewed: October 18, 2026. This article is general information, not legal advice. Radar detector and windshield rules are set by each state, so check your state's current statute before you mount one.

If you're thinking about buying a radar detector, or you're about to drive with one across state lines, the rules are simpler than most online lists make them look. For an ordinary car, the answer is "legal" almost everywhere. The exceptions are few, but they matter.

Short answer: are radar detectors legal, and where are radar detectors legal? They are legal in private passenger vehicles in most of the United States. Virginia and Washington, D.C. ban them. Federal rules ban them in commercial motor vehicles (generally trucks and buses rated at 10,001 pounds or more used in commerce) in every state, some states add their own limits for heavy vehicles (New York, for example), and military bases set their own rules. Jammers are a different device and are illegal. Even where a detector is legal, some states limit what you can attach to your windshield.

Jump to:

How radar detectors work, and why some places ban them

A radar detector is a receiver. It listens for the radio signals that police radar guns send out (and, on many models, the light pulses from laser speed guns) and warns you when it picks them up. It doesn't transmit anything itself.

That passive design is why most states leave detectors alone: owning a radio receiver isn't a crime. The places that ban them take the view that the device's only purpose is to help drivers avoid speed enforcement. A radar jammer is a different thing. It actively transmits to confuse police equipment and is treated far more harshly (see the FAQ below).

Where are radar detectors illegal?

In a private passenger car, radar detectors are illegal in Virginia and Washington, D.C. Elsewhere in the US there is no general ban for ordinary cars, though the vehicle-type and windshield rules below still apply.

Virginia (full guide). The ban covers driving on Virginia highways in a vehicle equipped with a detector, and the statute also makes it unlawful to use one or sell one in Virginia. A few narrow exceptions apply, including a device that has no power source and is not readily accessible to the driver or passengers (for example, a boxed unit in the trunk), and law-enforcement vehicles. The statute says no DMV demerit points are given for a violation, and the officer may take the device as evidence and return it later.

Washington, D.C. The District's rule is short and broad. It bans selling detectors in D.C. (§ 736.1) and using or possessing one in an automobile in the District (§ 736.2). The only listed exception is for vehicles and equipment of the US Armed Forces (§ 736.3). Because the rule covers possession, unplugging the detector isn't enough when you drive through D.C.

Military bases. Military installations set their own traffic rules, and radar detectors are widely reported to be banned on bases. We couldn't open an official base traffic regulation to quote, so check the rules for the specific installation (usually published by the base's security forces or provost marshal) before you drive onto one.

Full guide: Are Radar Detectors Legal in Georgia?

Yes. In Georgia, radar detectors are legal in private passenger vehicles. Georgia has no state law banning them in ordinary cars.

The exception is commercial vehicles. The Motor Carrier Compliance Division of Georgia's Department of Public Safety publishes a fact sheet titled "Attention Commercial Vehicle Drivers with Radar Detectors". It reprints 49 CFR 392.71 and notes that this "is a State and Federal law, which allows for civil and/or criminal prosecution of the commercial vehicle driver as well as the motor carrier." So if you drive a truck or bus that meets the commercial motor vehicle definition, a detector isn't allowed in the cab in Georgia.

Windshield mounts in Georgia. Georgia law forbids driving with "any sign, poster, or other nontransparent material upon the front windshield, side windows, or rear windows of such vehicle which obstructs the driver's clear view of the highway or any intersecting highway" (O.C.G.A. § 40-8-73(a)). A 2021 amendment (House Bill 165) added an exception for a mount supporting a "wireless telecommunications device or stand-alone electronic device" (terms defined in § 40-6-241), provided the mount is placed in a way that "minimizes obstruction of the driver's view." The amendment doesn't name radar detectors, so the safest choice is to mount a detector low on the windshield or on the dash, where it can't be said to block your view.

Some older guides claim detectors are banned in Georgia school zones or work zones. We could not find any Georgia statute that says so.

Full guide: Are Radar Detectors Legal in Michigan?

Yes. In Michigan, radar detectors are legal in private passenger vehicles. We found no Michigan statute banning them in ordinary cars, and Michigan is not one of the jurisdictions with a general ban.

As in every state, the federal rule applies to commercial motor vehicles, so a detector can't be used in, or even carried in, a truck or bus that counts as a CMV. Some older articles say Michigan bans detectors outright or sets special fines in school or construction zones. We found no law that supports those claims.

Windshield mounts in Michigan. Like most states, Michigan limits material on the windshield that blocks the driver's view. We couldn't open the official text of Michigan's windshield statute to check how it treats electronic devices, so mount the detector where it doesn't block your line of sight. If you're unsure, ask the Michigan Secretary of State or your local police.

Commercial trucks and buses: the federal ban

The federal ban applies to commercial motor vehicles in every state, including states where detectors are otherwise legal. It is part of the Federal Motor Carrier Safety Regulations:

  • Drivers may not use a detector in a CMV, or operate a CMV that is "equipped with or contains" one (49 CFR 392.71(a)). Simply having one in the cab breaks the rule, even if it's switched off.
  • Motor carriers may not require or permit a driver to break that rule (§ 392.71(b)).
  • What counts as a radar detector is defined broadly: any device to detect radio microwaves, laser beams "or any other future speed measurement technology" used by police (49 CFR 390.5). Under the same definition, a device carried outside the driver's compartment and completely inaccessible and inoperable while driving is excluded.

What counts as a commercial motor vehicle? Under 49 CFR 390.5, it is a vehicle used on a highway in interstate commerce to transport passengers or property that has a gross vehicle weight rating or gross combination weight rating of 10,001 pounds or more; or is designed or used to carry more than 8 passengers (including the driver) for compensation, or more than 15 passengers not for compensation; or carries hazardous materials in amounts that require placards. The federal rule is written for interstate commerce, but many states, Georgia among them, enforce the same rules as state law.

Windshield mounting rules

Even where a detector is legal, how you mount it can still get you a ticket. Many states restrict objects on the windshield. Two examples we checked:

  • Georgia: the windshield-obstruction rule and the 2021 device-mount exception described above.
  • California: Vehicle Code § 26708(a)(1) says a person "shall not drive any motor vehicle with any object or material placed, displayed, installed, affixed, or applied upon the windshield or side or rear windows," subject to listed exceptions. One exception allows a portable GPS in "a seven-inch square in the lower corner of the windshield farthest removed from the driver or in a five-inch square in the lower corner of the windshield nearest to the driver and outside of an airbag deployment zone." The section doesn't mention radar detectors, so in California a dash mount is the safer choice.

Rules like these are why many drivers use a dash mount, a rear-view-mirror mount or a low-profile hard-wired installation. Whatever you choose, keep the detector out of your direct line of sight and away from airbag deployment areas.

Before you buy or travel

  • Driving to or through Virginia or D.C.? Unplugging isn't enough. Virginia's exception requires the device to have no power source and be out of reach, and D.C.'s rule bans possession in the car. Put it in the trunk, or leave it at home.
  • Driving for work? If the vehicle is a CMV, a detector isn't allowed at all.
  • Don't treat a detector as permission to speed. It warns you about a signal. It doesn't change the speed limit or protect you from pacing, aircraft patrols or other enforcement methods.

State guides

Each guide quotes that state's statute and covers cars, commercial vehicles, jammers and windshield mounting:

A note on the FCC. Radar detectors are also regulated as equipment by the Federal Communications Commission. Under 47 CFR § 15.109(h), "Radar detectors shall comply with the emission limits in paragraph (a) of this section over the frequency range of 11.7-12.2 GHz," a rule the FCC adopted in 2002 after detectors were found interfering with small satellite (VSAT) terminals. It governs how detectors are built and sold, not where you may use one.

Related reading: window tint laws by state and which states allow lane splitting.

In which states are radar detectors illegal?

For ordinary passenger cars, Virginia and Washington, D.C. are the two US jurisdictions with a general ban. Virginia's ban is in Va. Code § 46.2-1079; D.C.'s is in 18 DCMR 736. Separately, federal rules ban radar detectors in commercial motor vehicles everywhere.

Are radar detectors legal in Georgia?

Yes, in a private passenger vehicle. Georgia has no general ban. They are illegal in commercial motor vehicles, a rule Georgia's Department of Public Safety enforces under 49 CFR 392.71.

Are radar detectors legal in Michigan?

Yes, in a private passenger vehicle. We found no Michigan law banning them in ordinary cars. As in every state, they are banned in commercial motor vehicles under federal rules.

Can a truck driver use a radar detector?

Not in a commercial motor vehicle. Under 49 CFR 392.71, a driver may not use a radar detector in a CMV, or even operate a CMV that contains one. That generally covers vehicles rated at 10,001 pounds or more used in commerce, plus some passenger and hazmat vehicles.

Are radar jammers legal?

Treat them as off-limits. Virginia's statute expressly covers devices that interfere with police speed measurement, D.C.'s rule covers devices that "counteract" police radar, and federal law prohibits willful interference with licensed or government radio communications (47 U.S.C. § 333).

Sources

Filed Under: Driving, Law

About Farrukh Shahzad

Farrukh Shahzad is the founder and researcher behind TodayinTrend. He is not a lawyer and does not give legal advice — he reads the statutes, court rules and official data, then explains what they actually say in plain English.

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