I watched a couple really interesting talks from this past Def Con. In one of the talks, Snoop Unto Them As They Snoop Unto Us, Null Agent points out that all Axon equipment (the company putting tasers on drones) share the same organizationally unique identifier (OUI) and communicate via Bluetooth Low Energy. When you pull your firearm or taser from an Axon holster, it can be set up to signal your bodycam to automatically turn on, for example. So by snooping on the BLE data channels you can look for Axon’s OUI and infer that a law enforcement officer is within your Bluetooth range (max 300ft or so in optimal conditions).
That’s all this script does. If it detects Axon equipment it plays a sound, alerts on your terminal, and logs the MAC address / time of encounter. I run it on my laptop in my living room with a super cheap Bluetooth adapter and I get notified when there are cops outside. Couple this with listening to your local police / public safety radio and you’ll never be surprised by a no-knock again.
How frequently can bluetooth scan for new devices? I wonder if one was to use a high gain 2.4ghz antenna if the range could be increased enough to detect cops from a moving vehicle.
Doing so would get around Virginia’s and DC’s radar detector laws as both laws state you aren’t allowed their speed guns but says nothing about detecting the cops themselves.
Bluetooth would not work well enough to detect a cop far away enough to get you to slow down while driving. Not a suitable replacement for a radar detector (and even those face similar problems)
You can adjust the wait between scans in the script, I have it set to 12 seconds by default. But if you set it to 1, I think I anecdotally found it complete a scan every 5-6 seconds with my setup. It detects cop cars driving by at night if I leave it on in my living room.