Green’s Dictionary of Slang

joe (hunt) n.

a fool, a general derog. term.

1909		T.A. Dorgan in Zwilling TAD Lex. (1993) 112: It’s a pipe that he works for a joe editor.
1965		B. Crump ‘Scrapwaggon’ in Best of Barry Crump (1974) 196: ‘Make you look a proper joe, wouldn’t it,’ observed Watcher.
1969		N. Hilliard A Night at Green River 58: What a joe they’d think he was, ringing to ask the name of his nearest neighbour.
1978		Maledicta II:1+2 (Summer/Winter) 117: Mr. Aylwin has a two-page section on ‘Vulgarity.’ [...] To Berkeley Hunt, however, he is able to add these other words for cunt, though he mixes up the terms used to describe female anatomy and those used only as insults (stupid berk): gasp & grunt, growl & grunt, Joe Hunt, sharp & blunt.
1981		G. Johnston Fish Factory 146: Everyone would laugh and make snide remarks. I’d feel a proper Joe Hunt.
1988		J. McDonald Dict. of Obscenity etc. 76: Joey is really Joey Hunt, a cunt.
1988		McGill Dict. of Kiwi Sl. 63/2: joe hunt a foolish person; rhyming slang with ‘cunt’.
2003		McGill Reed Dict. of N.Z. Sl. [as cit. 1988].

In phrases

make a joe of oneself (v.)

(N.Z.) to make a fool of oneself.

1963		Dominion (Wellington) 30 Sept. 4: [Heading] Player makes big ‘joe’ of himself. The [Wellington] club awards its Joey emblem to the player who, in the judgement of the reserves, makes the biggest ‘Joe’ of himself during the match [DNZE].
1988		McGill Dict. of Kiwi Sl. 63/2: joe a fool, or acting foolishly, in phr. make a joe of yourself; from derisive use of word to identify police in Victorian goldfields mid-C19.