Common sense will tell you two things, scanner later.
In your case, TN law requires only the showing of identification and badge is 
most common and readi;ly visible symbol of authority available in exigent 
circumstances. Of course the uniform could be a quick clue. common sense says 
that a uniformed or ununiformed man, with a gun is somebody to be listened to 
very carefully. if a leo you face arrest for noncompliance if aspproprite and 
possible, if a crook you face worse.
scanners. not in common use by most civilians and in many jurisdiction 
illegal in az motor vehicle w/o proper authorisation.
In amany cities, the traffic volume would lead to a lot of missed calls, 
because to hear everything you have to listen to everything.
And yes the public is losing the entetrtainment value of scanners as daily 
technology is improved.
 RW> were using a clear radio then he'd know that a crime
 RW> had been committed.  But most major police departments
 RW> don't want to allow people to hear what they are doing
 RW> so. . .
Civilians have no innate right tio know EVERYTHING.
--- Maximus 3.01
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