Green’s Dictionary of Slang

1. a dedicated villain who has (so far) escaped the gallows.

1788, 1796		Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn) n.p.: Scapegallows. One who deserves and has narrowly escaped the gallows, a slip-gibbet, one for whom the gallows is said to groan.
1817		Cobbett’s Wkly Political Register 6 Dec. 12/2: The scape-gallows went over to Halifax and gave himself up.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1828		Exeter & Plymouth Gaz. (Devon) 2 Feb. 2/2: Nor am I a scape-gallows (I use that gentlemanly word in its usual acceptation).
1837		Wexford Conservative 11 Feb. 4/2: Here the young scape-gallows [...] clenched his fist.
1841		Vindicator (Antrim) 13 Jan. 4/1: ‘It’s not to such a hair-brained scape-gallows that I am goin to be afther givin’ my daughter and my forty goold guineas’.
1850		Coleraine Chron. (Londonderry) 6 July 4/1: ‘Why, you young scapegallows, I’ll have you shot like a parcel of dogs!’.
1860		Dunfermline Sat. Press (Scot.) 24 Mar. 4/1: The ‘vile scape-gallows o’ the name o’ Hapworth’ [...] committed suicide.
1866		Sheffield Indep. 18 Jan. 3/3: A scape-gallows [...] who had once been under sentence of death, and narrowly escaped hanging, was charged with a murderous assault on the governor of Rye gaol.
1905		Sporting Times 28 Jan. 3/3: With the public taste for horrors [...] a second-hand gallows would be of real use to [...] a ‘scape-gallows’ and a retired hangman.
1913		Pall Mall Gaz. 17 July 5/3: His neighbours [...] finally drove the ‘scape-gallows’ to live and die [...] some miles away.

2. attrib. use of sense 1.

1818		M.L. Weems Drunkard’s Looking Glass (1929) 95: Take that! and that! and that too, you scape-gallows rascal.
1825		S. Woodworth Forest Rose II iv: What a scape-gallows wretch it must be! to tell such a lie!
1839		Champion (London) 6 Oct. 5/2: Is not six years long enough to have the execution or non-execution of a law dependant on the will of a set of scape-gallows commissioners?
1846		T.B. Thorpe Mysteries of the Backwoods 167: A tall, scape-gallows-looking fellow.
1853		Western Times (Devon) 4 June 8/1: You are a lazy, idle scape-gallows rogue.
1885		Salisbury Times 7 Mar. 2: The newspaper expresses [...] extreme disdain for the ‘scape-gallows’ rascals.
1891		Framlingham Wkly News 4 July 3/6: Fortunately medical science can distinguish between lunacy [...] and its scape-gallows counterfeit.