Green’s Dictionary of Slang

unfair, crooked (esp. by pre-arrangement).

1830		Ely’s Hawk & Buzzard (NY) 3 July 2/1: I saw one of Crazy John’s barney printers setting up a song with my name [...] as its author. This is done no doubt to decive [sic] the Public.
1903		A. Binstead Pitcher in Paradise 128: Those two getabits [...] will get up a dud or barney fight right under your nose.