Are any jamming devices legal for use in the United States?

The purchase, marketing or operation of any jamming device is prohibited in the United States of America, explains Federal Communications Commission. Jammers are banned under the Communications Act of 1934; they are only manufactured in the United States for the purpose of export or for sale to the federal government.

Any device used to interfere with lawful radio communications is considered an illegal jammer by the U.S. government; and, an individual faces up to $112,500 in fines, as well as jail time, for even a single offense. The FCC urges citizens to report any suspicious instances of radio interference, as well as any knowledge of existing unlawful devices.