Generally, most of the cases before the Supreme Court are heard by a division bench (2 or 3 judge members). An exception to this rule is a Constitution bench.
A constitution bench consists of at least five or more judges of the court which is set up to decide substantial questions of law with regard to the interpretation of the constitution in a case.
The provision for a Constitution bench has been provided in the Constitution of India under Article 143. It is the Chief Justice of India who is constitutionally authorized to constitute a constitution bench and refer cases to it.
Constitution benches are set up when the following circumstances exist:
1) When a case involves a substantial question of law pertaining to the interpretation of the Constitution [Article 145(3)]. Article 145(3) provides, “The minimum number of Judges who are to sit for the purpose of deciding any case involving a substantial question of law as to the interpretation of this Constitution or for the purpose of hearing any reference under Article 143 shall be five.”
2) When President of India has sought the Supreme Court’s opinion on a question of fact or law under Article 143 of the Constitution. Article 143 of the Constitution provides for Advisory jurisdiction to the Supreme Court of India. As per the provision, the President of India has the power to address questions to the Supreme Court, which he deems important for public welfare. The Supreme Court upon reference advises the President by answering the query. However, such referral advice by the apex court is not binding on the President, nor is it ‘law declared by the Supreme Court’.
3) When two or more three-judge benches of the Supreme Court have delivered conflicting judgments on the same point of law, necessitating a definite understanding and interpretation of the law by a larger bench.
The Constitution benches are set up on ad hoc basis as and when the above-mentioned conditions exist.
Most of the landmark cases, such as AK Gopalan v. State of Madras, Kesavananda Bharati v. State of Kerala, etc., in which the court settled the law by some degree of finality were decided by the Constitution benches.