The Poe Paradox is a corollary to Poe's Law. It states that:
"In any fundamentalist group where Poe's Law applies, a paradox exists where any new person (or idea) sufficiently fundamentalist to be accepted by the group, is likely to be so ridiculous that they risk being rejected as a parodist (or parody)."
The term was first used by RationalWiki editor The Lay Scientist to describe an apparent paradox in the management of editing rights at Conservapedia:
A poe paradox: any new member of the Conservapedia project who's not as Conservative as them is liable to be chucked out. However, any new member who is as Conservative as them is in serious danger of being called a parodist, and chucked out.