Green’s Dictionary of Slang

(US Und.) one who passes counterfeit currency.

1880		N.Y. Times 17 Aug. 2/2: Two other local detectives were stationed one at each bank with instructions to arrest the ‘layer down,’ as the presenter of a forged check is called.
1889		S. Bailey Ups and Downs of a Crook’s Life 23: Several times the ‘layer down’ was caught.
1893		J. Hawthorne Confessions of Convict 240: Lowest in rank in such a gang is the ‘layer-down,’ whose business it is to present the forged paper.
1952		C. Hamilton Men of the Und. 249: Half a dozen parolees who served as layers-down.
1956		R.T. Hopkins Banker Tells All 165: Like all makers of ‘queer’ coins he dare not pass them himself but was forced to hand them over to ‘layers-down’.