This is bad. The Register reports that car thieves in the UK are now using illegally imported GPS jammers to avoid the GPS tracking systems now found in many autos. Consider the implications — bank robbers and sex offenders with jammers, bleed over from the signals affecting emergency services, etc. Not good.
As far as I can tell, there isn’t a specific US law targeting such devices, though they do seem to fall under the broadly worded Communications Act of 1934, which makes it illegal to operate “transmitters designed to jam or block wireless communications.”
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