I grew up in Reno, NV--born 1934--At that time, "star" was used to refer to a cop, as in "Watch out, there's a 'star' behind us," when driving, or "here comes a 'star'," if we were doing something less than legal.  It was a respectful term.  It seemed to have gotten replaced by the less respectful sounding "fuzz" by the late 40's or early 50's, somewhat earlier than the decidedly negative "pig" of the hippy era. 

Patty Slayton