Canon 1323

1. A res iudicata possesses stability of law so it can only be

challenged by a complaint of nullity, restitutio in integrum or

the opposition of a third party. 2. A res iudicata settles an

issue between the parties and gives rise to an action for execution and an exception of res iudicata, which the judge can declare ex officio to prevent a new introduction of the same case.