Green’s Dictionary of Slang

one who accuses another person unfairly, and/or through the provision of faked evidence.

1931		intro to H. Leverage ‘The White Moll’ in Prison Stories May–June 🌐 Bradshaw, the D. A., was a born framer—and he was getting away with it.
1951		(con. 1941) E. Lambert Twenty Thousand Thieves 160: Go Through invented a name for Crane that the whole battalion immediately took up: Framer Crane.