Board members knowingly participated in wrong doing.
The nonprofit organization acted outside of, or in someway inconsistent with, its bonafide status as a nonprofit organization.
Board members had either reason to know of wrongdoing or were negligent in not knowing of wrongdoing by the organization.
Tort:

A "tort" is a private or civil action, not a criminal act. Generally, an action in tort involves a violation of a duty imposed by law upon persons having a legal relation to each other involved in a particular transaction. There is no action in tort if there is no resulting economic loss.

There must always be a violation of some duty owed one party to the other, and the duty must arise by operation of law and not merely by agreement of the parties or contract.
Elements of a tort action: (1) existence of a legal duty between the parties; (2) a breach of that duty; and (3) damages proximately resulting from that breach. All elements must be proved.
IX. A RESOURCE GUIDE