For the engagements that LEO's required, the Mini-14 GB was ideal. Average patrolmen have never been superb marksmen capable of shooting a baddie in the head while he had a human shield nor should they ever try - such an action was better left to better trained officers. Yet, as the militarism of the police force continued, the Mini lacked the panache of a good AR. Sure, the AR was more accurate as a general rule, but at police ranges, it didn't matter. Twice as accurate at 30 feet hardly matters. But the AR allowed police to become more paramilitary and so departments went that route.
Yeah, that's real simplistic and I don't want to get into an argument about officers in combat attire doing traffic stops or AR's vs Mini's. My point was that the Mini's could have easily been retained by the forces that surplussed them - they are all in virtually new condition except for stock wear. There was no need to spend so much more money on AR's given the needs of the force and the average patrolman.
Of course, I am glad so many departments surplussed their GB's and magazines. Mine was acquired cheaply and I am pleased with it. I have owned three AR's, a Bushmaster, a Rock River, and a Stag. I own none of them now yet still have the Mini. I prefer it and it has been utterly reliable and is an accurate rifle. Others may not be, but mine is and that is all I need or care about. When I'm in the woods, I just don't need an AR festooned with rails, optics, monopods, lasers and the like. You prefer an AR, great, enjoy. I know I'm in the minority, but I select my rifles not out of popularity but out of need.
In any case, Ruger was right when he decided we don't need a Mini with flash hider, bayonet lug, or high magazines for hunting. I guess that's why my Pedersen 3500 lacks all of those. That mini on the other hand is not used for hunting.