I had a very pleasant chance encounter today with retired Philadelphia Police Officer Bob Hurst who long ago served as head of the department’s “Granny Squad”. At great risk to their lives and safety, Bob and his colleagues on the squad spent years disguised as old women, derelicts, drunks and otherwise vulnerable victims trolling the streets of Philadelphia for armed robbers and violent felons. (The picture above is purportedly of Bob in disguise.) When attacked, the decoy officer and his back up team would arrest the assailant. Sometimes they were required to use deadly force. In the late 1970s and early 1980s,...