Doorstep Crapper

A "doorstep crapper" (or pooper) is a person who does something and then denies it, despite the strong evidence they did indeed.

Comes from the analogy of someone pooping on a doorstep, and upon confrontation says "Nobody's pooping on your doorstep, stop overreacting." Before again pooping on the doorstep later.

Doorstep crappers are hypocritical and act like they are innocent despite being guilty liars.

Example 1:
Person: Hey, Bob, stop stealing my cookies.
Bob: Nobody's stealing your cookies, stop complaining, nobody cares. *proceeds to steal Person's cookies*
Person: I see you Bob, stop being a doorstep crapper.

Example 2:
Kid: Hey, stop copying my work!
Peer: I'm not copying your work! *blatantly copies Kid's work again*