Cell phone signal jamming by private citizens is a federal crime in the United States. It is banned by the Communications Act of 1934 and carries penalties of both prison time and monetary fines.
Jamming cell phones is illegal under the same laws that ban interference with licensed radio stations and other authorized wireless signals. Manufacturing, importing, selling and advertising cell phone jamming devices for civilian use is also illegal in the United States. Federal government employees and law enforcement officers are the only people permitted to possess or operate cell phone jammers in the United States. Jamming devices owned by private citizens are subject to government seizure.
These restrictions apply on private property, including religious buildings such as churches. This is because property owners do not have any rights to the wireless spectrum licensed by legitimate operators, even when it is used on their property.
Legal options to limit cell phone use on private property include banning the devices from the property and passively blocking wireless signals. Building materials such as steel and thick concrete in walls and ceilings limit or block wireless signals from entering and are not illegal. These methods are legal because they do not interfere with a licensed operator’s wireless spectrum rights.