Yes.
Only if he has his radar gun on. Radar detectors are not cop detectors.
Radar detectors are legal. Radar scramblers however are NOT legal.
The best radar detectors on the market are made by Beltronics. Beltronics is a leading manufacturer of the Vector, Professional, and Express radar and laser detectors.
Laser detectors detect laser beams used by law enforcement to measure speed, while radar detectors detect radio waves used by police radar guns. Laser detectors are more precise but have a shorter range compared to radar detectors. It's recommended to have both types of detectors for comprehensive coverage.
Radar detectors are legal to use for all non-commercial vehicles in 49 states. Washington, DC and Virginia are the only two states that radar detectors are banned in the United States. Radar detectors used in commercial vehicles are illegal.
Radar Detectors in Oklahoma: Radar detectors are legal to use in Oklahoma.Laser Jammers in Oklahoma: Laser jammers are illegal to use in Oklahoma.Courtesy of: http://www.1stradardetectors.com/radar-detector-laws.php
Radar detectors are legal to use in Nevada, but as you stated they are illegal to sell.
Valentine radar detectors are the most popular for their sounds.
Radar detectors are legal for passenger vehicles in North Carolina. However, they are prohibited for use in commercial vehicles. It is important to note that while radar detectors are legal, the use of radar jammers is illegal in North Carolina and throughout the United States. Radar detectors are devices that can detect radar signals emitted by police radar guns, while radar jammers are devices designed to interfere with or block radar signals.
Beltronics offers the best performing radar and laser detectors on the road, including the Professional Series models.
You can fix radar detectors for cheap by fixing them yourself. You can learn how to fix radar detectors yourself at the eHow website. Once on the page, type "How to fix radar detectors" into the search field at the top of the page and press enter to bring up the information. Alternatively, you can also learn how to repair this item at the Fixya website.