Yes, CHAMPERTIES is a Scrabble word!

Letter values in Scrabble US: C 3, H 4, A 1, M 3, P 3, E 1, R 1, T 1, I 1, E 1, S 1.

Is it a valid word?

CHAMPERTIES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

an unethical agreement between an attorney and client that the attorney would sue and pay the costs of the client's suit in return for a portion of the damages awarded