The concept of res judicata is embodied under section 11 of the Code of Civil Procedure, 1908. It is also known as the rule of conclusiveness of judgment, as it concludes a judgment in a way that no further litigation is possible on that particular matter. Therefore, it serves the maxim 'Interest Republicata Ut sit finus litium' which means that it is in the interest of the state that litigation must come to an end.

The word 'Res' can be interpreted as 'everything that may form an object of rights and includes an object subject-matter or status' and the term 'judicata' means adjudged, adjudicated or decided. Thus, the term 'res judicata' means a matter adjudged, a thing judicially acted upon or decided by judgment.

Section 11 of Code of Civil Procedure,1908

Section 11 of the Code of Civil Procedure, 1908 provides the doctrine of res judicata. It states 'No courts shall try any suit or issue in which matter directly and substantially in issue has been directly and substantially in issue in a former suit between the same parties, or between parties under whom they or any of them claim, litigating under the same title in a court competent to try such subsequent suit, the suit in which the issue has been subsequently raised, and has been heard and finally decided by such court'.

Essentials of res judicata

The following are the essential conditions required to apply the doctrine of res judicata;

• There should be two suits: former and subsequent suit.
• Parties must be the same in both suits.
• Parties must be contending under the same title.
• The matter in both suits must be directly and substantially the same.
• The former court must be competent to try such subsequent suit.

Detailed Explanation

• Former and subsequent suit: For the doctrine of res judicata to apply, there must be two suits: a former suit instituted before and a subsequent suit instituted after the former suit. According to explanation 1 of Section 11, when two suits are filed, the former suit will be the one that is heard and finally decided before the other suit.
• Same parties: Parties in both suits must be the same. That is, the parties in the subsequent suit must be the same as the parties in the former suit.
• Same title: Parties in both suits must be contending under the same title or derive their title from the parties in the previous suit.
• Directly and substantially: Matters in both the suits must be directly and substantially in issue, not collaterally and incidentally. This means that the matter must be alleged by one party and either accepted or rejected by the other party. Opinions or observations given by judges on a particular matter are matters collaterally and incidentally in issue.
• Competent court: The former court must be competent to try the subsequent suit as though the subsequent suit was instituted in the former court at the time and date when the former suit was instituted. An exception to this is Explanation 8 of Section 11.

Legal Maxims on Res Judicata

• Exceptio res judicata: A previous judgment is a bar to a subsequent suit. An exception whereby the defendant can claim that the matter has already been adjudged and cannot be revisited.
• Res judicate pro veritae accipitur: A matter adjudged is taken for truth. A judgment given by the court will be true and everyone should follow it.
• Nemo debit bis vexari pro una et eadem causa: No one should be troubled twice for the same cause.
• Interest republicae ut sit finis lituim: It is in the interest of the state that litigation must come to an end.

Constructive Res Judicata

The principle of constructive res judicata is inscribed in Explanation 4 of Section 11. It provides that any matter which might and ought to have been made a ground of defense or attack in a former suit shall be deemed to have been directly and substantially in issue in such suit. This creates a legal fiction where even though the matter was not raised in a former suit but could have been raised with due diligence, it will be considered to be already raised and barred in a subsequent suit.

Explanation 8 of Section 11

Explanation 8 of Section 11 states: "An issue heard and finally decided by a court of limited jurisdiction, competent to decide such issue, shall operate as res judicata in a subsequent suit, notwithstanding that such court of limited jurisdiction was not competent to try such subsequent suit or the suit in which such issue has been subsequently raised." Even if a court of limited jurisdiction hears and finally decides on some issue, it will operate as res judicata in a subsequent suit filed in a court of ordinary jurisdiction. This exception acts as a saving clause.

Representative Suit and Res Judicata

In a representative suit, one person files a suit on behalf of many others interested in the matter. Once such a suit is decided, it will bind not only the actual party contesting but also those on whose behalf the suit was contested. Subsequent suits on the same matter by others will be barred under res judicata.

Public Interest Litigation and Res Judicata

Case: Forward Construction Company vs. Prabhat Mandal (Andheri) (1985) SC It was observed that res judicata applies to public interest litigation as well.

Purpose of res judicata
The purpose is to prevent a multiplicity of proceedings. The principle of res judicata puts a bar upon similar suits or suits of a similar nature, this in turn reduces the burden upon courts.

It avoids conflicting judgments, that is when multiple suits of a similar nature are instituted then it might be possible that two different courts may pronounce different judgments accordingly. This can result in conflicting judgments. Therefore, to avoid such conflicting judgment the principle of res judicate is applied.

Prevents unnecessary burden on the courts. 'Justice delayed is justice denied'. Thus, timely disposal of cases provides quick justice to the distressed and this is ensured by the application of res judicata.

Conclusion
Hence, to conclude the principle of res judicate is imperative and required in the courts to avoid confusion or conflicting judgments. Res judicata under section 11 of Code of Civil Procedure, 1908 applies only to civil matters but the broad concept of res judicate applies to not only civil but also criminal matters.

Therefore, it is an imperative doctrine that is well regarded in the court of law, without which there will be conflicting judgments, multiplicity of proceedings, and unnecessary burden upon the courts.