As a very young man in college, I worked midnights in a c store. One night I observed a guy concealing a bottle of wine. Dummy that I was, I called the cops and locked the thief and myself in the store to await police. Unbeknown to me, the guy had a ball peen hammer up his coat sleeve. After threatening me he proceeded to bust out glass of the door and ran off. The hammer could just as well been a gun. I learned my lesson about locking myself up with criminals.
well, that’s the beauty of a tandem-door mantrap: the perp enters the inner door of the mantrap, the trap is sprung and both the inner and outer door of the mantrap are locked until the cops arrive ...