Green’s Dictionary of Slang

(US) tough, ‘strong-arm’; also as n.

1928		J. Callahan Man’s Grim Justice 34: ‘Kelly’s a raw-jawed dangler,’ I thought. ‘Most of the crooks are afraid of him.’.
1930		‘Dean Stiff’ Milk and Honey Route 24: The rawjawed teameos and muckers, dynoes and shantymen who built that railroad.
1937		(con. 1905–25) E.H. Sutherland Professional Thief (1956) 43: He may operate on a murder, raw-jaw, or rip-and-tear basis.
1947		N. Algren Neon Wilderness (1986) 116: This was the only time I used raw-jaw methods.
1961		M. Braly Felony Tank (1962) 64: We didn’t think you were in enough trouble to have to go that rawjaw.
1975		J. Carr Bad (1995) 88: Smitty, a fake Muslim and a real raw-jaw artist.
1976		M. Braly False Starts 124: They deplored violence and dismissed it scornfully as ‘rawjaw’.