(A) Civil P.C. (5 of 1908) , S.11, O.14 R.1, O.14 R.2— Res judicata - Issue as to - Whether can be decided as preliminary issue - Plea of res judicata may in an appropriate case be determined as a preliminary issue when neither a disputed question of fact nor a mixed question of law or fact to be adjudicated for resolving it. Court while undertaking an analysis of the applicability of the plea of res judicata determines first, if the requirements of S. 11 CPC are fulfilled and if this is answered in the affirmative, it will have to be determined if there has been any material alteration in law or facts since the first suit was decreed as a result of which the principle of res judicata would be inapplicable. Submission that res judicata can never be decided as a preliminary issue, not tenable. In certain cases, particularly when a mixed question of law or fact is raised, the issue should await a full-fledged trial after evidence is adduced. In the present case, a determination of the components of res judicata turns on the pleadings and judgments in the earlier suits which have been brought on the record. The issue is argued on that basis before the Trial Court and the First Appellate Court followed by two rounds of proceedings before the High Court. All the documentary material necessary to decide the issue is before the Court and arguments is addressed by t....