By default I assume law enforcement is exaggerating for effect, but lot of emergency radios are on 800Mhz, AT&T (as one example) uses 850Mhz, so it wouldn't be hard to imagine a radio transmitter that cuts a wide swath (e. g., jammer) and interferes with other radios.
This depends on the jammer. They range from jam-almost-everything, to jamming only specific wavelengths (configurable or not), to jamming only specific protocols (which is more technically a DOS attack, but still functions like jamming).
Assuming the driver was using a wavebubble, it's likely that it would jam police radios as well (depending on configuration).
I understand how they work just fine. Which part of my statement implies a narrow-band device? Perhaps I was unclear, but I think that I worded it such that a wide-band device was implied ("wide swath").
Regardless, jammers can be narrow-band or wide-band depending on the goal. The device in the article sounds to be wide-band, but that doesn't define the entire category.
