Green’s Dictionary of Slang

(N.Z. prison) to lose one’s temper or to laugh.

1999		D. Looser ‘Boob Jargon’ in NZEJ 13 28: cripple out v. To ‘go nuts,’ lose one's temper.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 49/1: cripple out v. 1 to lose one's temper. 2 to laugh.