The NYPD is spending $390 million on a new radio system that will encrypt officers’ communications — reversing a near-century-old practice of allowing the public and the press to listen to police dispatches.
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From a legal standpoint does that change things? Especially if the keys aren't intended to be public?
Not until you use it to expose police wrongdoing.
I assume it depends on where you live, but police scanner radios have been around and on the shelf at stores for half a century. I imagine it's a legal grey area similar to radar detectors.