Legal Question in Civil Litigation in California

Maybe. It would depend upon the circumstances.

Stopping payment on a check is not actionable by itself. But breaching a contract is. If you had a contract that required you to make a payment, and if you made the payment via check, then stopping payment on that check was probably a breach for which you can be sued successfully.

Sure they can sue you. In addition for a breach of an underlying contract that the check was payment for, they can pursue you under Civil Code section 1719 if they prove that your stop payment was not the result of a good faith dispute with the payee.

You may want to read the entire statute, as there are statutory penalties that enhance the amount of the recovery. http://law.onecle.com/california/civil/1719.html