Green’s Dictionary of Slang

versing law n.

[verse v. + law n. (1)]

(UK Und.) those confidence tricks that focus on the use of counterfeit gold to entrap the victim.

[UK]Greene Notable Discovery of Coosnage 38: In Versing law. He that bringeth them in, the Verfer The poore Countrie man, the Coofin And the dronkard that comes in, the Suffier.