How Rude! Do you think that I would actually give you a lecture or legal opinion simply based on your innocent sounding question? ...
Hell Yes, I Would - and if needed, I'll do it again, whether you ask or not. It would be far worse if nobody had the courage to speak up.
I refer you first to the FCC Regulations on the subject, quoted and referenced at the bottom of the reply. There is a VERY GOOD REASON why nobody sells or imports jamming devices like that into the United States, because they are very illegal.
I would strongly suggest you drop all thoughts as to buying or installing them. It would be a fun device to keep people from making or receiving cell calls and interrupting your City Council meetings.
But let's say someone has a heart attack while alone in a stall in the public restroom right outside the Council Chambers, and they die while trying to call 911 for help from their jammed cellphone. The minute someone figures it out (and with CSI and NCIS giving people pointers on where to look, someone will check the phone and see the failed calls in the Outgoing Calls log) I guarantee you that all holy hell is going to break loose.
Or there is a disturbance in the Council Chambers, and a local policeman is delayed in making his radio call for backup and assistance. Or a commercial airplane making an instrument approach into the local airport in bad weather or heavy fog is 1/4 mile from the runway, and suddenly sees his whole instrument landing beacon system go blank ...
The type jammers used for this service are not very selective, they will wipe out all communications over a broad spectrum of radio frequencies and services including commercial, industrial, public safety, and aeronautic services, not just the narrow segments serving cellular telephone communications.
And if you are worried about bugging or malicious transmissions, you are just going to have to hire an expert to actively sweep for them. They can be anywhere in the electromagnetic spectrum, from DC to light, and a cellular jammer will probably miss the intended target.
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop Electrician for Westend Electric - CA7267005737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545 Spamtrapped address: Remove the python and the invalid, and use a net.