Green’s Dictionary of Slang

1. (orig. US Und.) of a prostitute, luring a client either to a room or a deserted alley, hallway etc. and then, instead of having sex, the client is beaten and robbed by a male accomplice, who may just strike, but may also pose as an aggrieved father, lover, brother etc; also attrib.

a.1954		‘Mexicana Rose’ in D. Wepman et al. Life (1976) 41: I’ll play the Murphy to the point of death.
1965		C. Brown Manchild in the Promised Land (1969) 167: Reno briefed me on our way downtown for my first Murphy lesson.
1966		J. Mills Panic in Needle Park (1971) 42: Mike found the Murphy game [...] considerably less harrowing than his old profession as a Badger Man. In that scheme he had worked with a prostitute, waiting for her to get a John into her room, then barging in and announcing angrily that he was the girl’s husband and was going to take the John apart limb by limb. Then he allowed his fury to be stilled by cash.
a.1967		‘Sporting Life’ in D. Wepman et al. Life (1976) 162: There are Miss Murphy walkers – oh, they’re convincing talkers – / Yes, everyone wants to be slick.
1968		J. Hersey Algiers Motel Incident 107: The Murphy game [...] is a big crime in Detroit.
1975		E. Torres Carlito’s Way 14: A first-class Murphy game I used to run [...] with the tricks looking for whores.
1989		J. Morton Lowspeak.
1990		S. Morgan Homeboy 25: She palmed Joe a twenty, his cut of the Murphy, as any bunko prostitution game was called.

2. (US) a swindle in general.

1965		Time 16 Apr. 16: ‘The Murphy Game’ is underworld argot for a slick maneuver in which a victim puts his cash in an envelope and gives it to the con man, who makes a fast sleight-of-hand switch and hands back an indentical envelope stuffed with newspaper strips.
1969		‘Iceberg Slim’ Pimp 32: I knew I would give ‘Party’s’ version of the ‘Murphy’ a whirl.
1972		O. Hawkins Ghetto Sketches 83: First thing I know, I’d been rooked out of my jade by some slick-talkin’ Armenian cats runnin’ the most sophisticated Murphy I’d ever encountered.

3. (US und.) street extortion by a fake ‘police officer’ [var. on sense 1 but note Murphy n. (2)].

1971

R. Woodley Dealer 127: ‘Hey, have you ever heard of the Murphy game? You know what the Murphy is on the street? Somebody walks up and flashes a badge, and he is not the police, and he takes you off. That’s called the Murphy’.