Green’s Dictionary of Slang

1. a justifiable arrest; usu. in the tongue-in-cheek phr. it’s a fair cop guvnor, put the bracelets on...

1881		Dly Gaz. for Middlesborough 4 Oct. 4/4: When witness remarked that it was a fair ‘cop’ Mrs Peacock appeared very much flurried.
1887		Sunderland Dly Echo 6 Apr. 3/1: McFarlane [...] got in, came out, and was caught [...] When arrested, said ‘Don’t badly use me; it is a fair cop’.
1899		E.W. Hornung Amateur Cracksman (1992) 33: All right, guv’nor [...] don’t excite. It’s a fair cop.
1905		Sporting Times 7 Jan. 1/1: Larf? So would you. I’m really innercent of this ’ere. The other times, it was a fair cop, an’ yet yer got me orf!
1918		‘Sapper’ Human Touch 79: Put the pop-gun away, guv’nor [...] It’s a fair cop, and it might ruddy well go hoff.
1925		E. Jervis 25 Years in Six Prisons 44: It was a ‘fair cop,’ as the boys call it.
1932		D.L. Sayers Have His Carcase 127: Lord, Inspector! How you startled me! All right, it’s a fair cop.
1940		J.G. Brandon Gang War 91: Most arrests by the inspector seemed to be accepted philosophically as a ‘fair cop’.
1956		R.T. Hopkins Banker Tells All 76: ‘It’s a fair cop,’ he moaned.
1961		‘Frank Richards’ Billy Bunter at Butlins 208: It’s a fair cop, and I ain’t giving no trouble.
1976		H. Leonard Time Was (1981) Act I: Of course there were burglars [...] And when you caught them they said: ‘It’s a fair cop, I’ll come quietly’.
1982		J. Sullivan ‘The Long Legs of the Law’ Only Fools and Horses [TV script] Well I’ll come quietly, miss – it’s a fair cop.
1991		Desperate Dan Special No. 7 28: It’s a fair cop, Guv!
2005		www.bristol.indymedia.org 20 Oct. 🌐 [heading] It’s a Fair Cop. Inspector’s Honesty Scunners G8 Case in Glasgow.

2. any situation seen as fair and about which there is no complaint.

1896		A. Morrison Child of the Jago (1982) 182: It’ll be a fair cop for ’im [...] ’E’s treated us all pretty mean, one time or another.
1900		Bulletin (Sydney) 4 Aug. 13/1: Whitewash: My ole man’s goin’ ter China. I call it a fair cop bein’ paid fer stoushin’ Chows.
1914		E. Pugh Cockney At Home 162: I tell you I thought I was on a fair cop.
1919		Marvel 3 Mar. 16: Well, it was a fair cop.