Green’s Dictionary of Slang

outlaw v.

[outlaw n. (3)]

of a prostitute, to operate independently of a pimp.

[US]R. Gover JC Saves (1979) 55: Odessa you such a strong-strong broad, outlawin like that.
N. Stone Tricks of Trade [film] I don’t have a pimp. I outlaw [HDAS].