A radar detector is an electronic device or appliance used to detect the radar waves. The ones used nowadays are capable of detecting signals of various wavelength bands, including 'K', 'X', 'K_u' and 'K_a'. However, they are able to detect only the Doppler radar. They catch the electromagnetic waves produced by the radar guns using a 'superheterodyne receiver' and raise an alarm. Laws in Different Countries To have a radar detector installed in a vehicle is termed illegal under the laws of many countries. It could result in it being seized, and the user might have to pay a fine as per the rules. The following points provide information regarding the laws of different countries.

• United Kingdom: It is legal to use this device in the United Kingdom; however, as per the 'Wireless Telegraphy Act' passed in 1949, technically it cannot be used.
• Australia: Its use is termed illegal in Australia, except for the state of Western Australia. A person possessing this appliance might have to pay a fine, up to AUD 1200, and can earn as many as 9 demerit points.
• Canada: It can be used only in the states of British Columbia, Alberta, and Saskatchewan. Substantial fines are imposed by the police for its illegal possession, in the other states of Canada.
• Belgium: Using radar devices is illegal in Belgium. In the year 2006, a vehicle worth EUR 75,000 was seized, and the driver's license was suspended for 3 months for illegal possession.
• Germany: It is illegal to use this device in Germany. Possession results in confiscation and destruction, along with a fine of EUR 75, and a 4 point deduction.
• Greece: Illegal possession here leads to driving license suspension for 30 days, a fine of EUR 2000, and car registration license suspension for 60 days.
• France: It is illegal to use radar equipment in France. Even if the device is not in active use, police can confiscate it and impose heavy fines on the user.
• Ireland: The law under which the detectors are confiscated in Ireland is known as 'Speed Meter Detectors'. Although the penalty amount is not fixed, confiscation of the appliance and imposition of a hefty fine could be the consequences of illegal possession.
• Switzerland: Here, the devices are confiscated and destroyed if possessed illegally.

State Laws In the state of Virginia and the US capital city of Washington D.C., the possession of a radar equipment is termed illegal. As per the state laws of New York, Illinois, and New Jersey, it is illegal to carry the appliance in commercial vehicles (vehicles weighing over 4,500 kg). In the states of California, Minnesota, and New York, the items which obstruct the vision of the driver are prohibited by law. The radar equipment come under the category of these items, and thus it is indirectly prohibited. Earlier, the illegal possession was penalized by confiscation of the device itself. However, confiscation results into the violation of property rights. Thus, even if the equipment is found in the vehicle, it is returned to the owner after entering its description (i.e., model, make, and serial number) on the ticket. Radar technology is used in the form of ground penetration radar equipment along with that in the radar detectors. With the invention of the radar, laws were made to prevent the misuse of this technology. Radar detector laws of different countries mentioned above would help in avoiding a penalty. In some countries, the use is completely banned, while few others permit its usage without any legal clauses attached to it. Thus, one should understand the laws of his respective country/state and follow them.