The doctrine of res judicata is provided in Section 47, Rule 39 of the Rules of Court:
SEC. 47. Effect of judgments or final orders. – The effect of a judgment or final order rendered by a court of the
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(b) In other cases, the judgment or final order is, with respect to the matter directly adjudged or as to any other matter that could have been raised in relation thereto, conclusive between the parties and their successors in interest by title subsequent to the commencement of the action or special proceeding, litigating for the same thing and under the same title and in the same capacity; and
(c) In any other litigation between the same parties or their successors in interest, that only is deemed to have been adjudged in a former judgment or final order which appears upon its face to have been so adjudged, or which was actually and necessarily included therein or necessary thereto.
The doctrine of res judicata thus lays down two main rules which may be stated as follows: (1) The judgment or decree of a court of competent jurisdiction on the merits concludes the parties and their privies to the litigation and constitutes a bar to a new action or suit involving the same cause of action either before the same or any other tribunal; and (2) Any right, fact, or matter in issue directly adjudicated or necessarily involved in the determination of an action before a competent court in which a judgment or decree is rendered on the merits is conclusively settled by the judgment therein and cannot again be litigated between the parties and their privies whether the claim or demand, purpose, or subject matter of the two suits is the same or not. These two main rules mark the distinction between the principles governing the two typical cases in which a judgment may operate as evidence. In speaking of these cases, the first general rule above stated, and which corresponds to the aforequoted paragraph (b) of Section 47,[24] is referred to as “bar by former judgment” while the second general rule, which is embodied in paragraph (c) of the same section, is known as “conclusiveness of judgment.”[25]
In Lopez v. Reyes,[26] we further elaborated the distinction between the two:
The doctrine of res judicata has two aspects. The first is the effect of a judgment as a bar to the prosecution of a second action upon the same claim, demand or cause of action. The second aspect is that it precludes the relitigation of a particular fact or issues in another action between the same parties on a different claim or cause of action.
The general rule precluding the relitigation of material facts or questions which were in issue and adjudicated in [a] former action [is] commonly applied to all matters essentially connected with the subject matter of the litigation. Thus, it extends to questions “necessarily involved in an issue, and necessarily adjudicated, or necessarily implied in the final judgment, although no specific finding may have been made in reference thereto, and although such matters were directly referred to in the pleadings and were not actually or formally presented. Under this rule, if the record of the former trial shows that the judgment could not have been rendered without deciding the particular matter, it will be considered as having settled that matter as to all future actions between the parties, and if a judgment necessarily presupposes certain premises, they are as conclusive as the judgment itself. x x x”[27] (Italics supplied.)
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