IIRC, for a brief time in the 60s Dallas police would sit with shotguns in the back of likely-target convenience stores. Armed robbers walked in but didn't walk out, and convenience store robberies screached to a halt.
Like most common sense, inexpensive and effective ideas, it was quickly shut down by politicians, who ultimately replaced it with the combo of sacrificial clerks and "No guns allowed" stickers that works so well today.
"in the 60s Dallas police would sit with shotguns in the back of likely-target convenience stores. Armed robbers walked in but didn't walk out,"
I like it! Sort of the Roach Motel style of law enforcement. Some bugs need killing.
Now we're talking'!
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