ESTOPPEL - (estopped) A bar which precludes someone from denying the truth of a fact which has been determined in an official proceeding or by an authoritative body. An estopple arises when someone has done some act which the policy of the law will not permit her to deny.
In certain situations, the law refuses to allow a person to deny facts when another person has relied on and acted in accordance with the facts on the basis of the first person's behavior.
There are two kinds of estoppel.
Collateral estoppel prevents a party to a lawsuit from raising a fact or issue which was already decided against him in another lawsuit.
Equitable estoppel prevents one party from taking a different position at trial than she did at an earlier time if the other party would be harmed by the change.
