By an act of Parliament:
According to Article 126 of the Constitution, when the office of the Chief Justice of India is vacant or when the Chief Justice is by reason of absence or otherwise unable to perform the duties of his office, the duties of the office shall be performed by such one of the judges of the court as the President may appoint for the purpose.
Article 127 lays down that, if at any time there should not be a quorum of the judges of the Supreme Court available to hold or continue any session of the court, the Chief Justice of India may, with the previous consent of the President and after consultation with the Chief Justice of the High Court concerned, request In writing the attendance at the sittings of the court, as an ad hoc Judge, for such period as may be necessary, of a judge of a High Court duly qualified for appointment as a Judge of the Supreme Court to be designated by the Chief Justice of India.
Further, Article 128 provides……… the Chief Justice of India may at any time, with the previous consent of the President request any person who has held the office of a Judge of the Supreme Court or of the Federal Court or who has held the office of a Judge of a High Court and is duly qualified for appointment as a Judge of the Supreme Court and every such person so requested shall, while so sitting and acting, be entitled to such allowances as the President may by order determine and have all the jurisdiction, powers and privileges of, but shall not otherwise be deemed to be a Judge of that court.
Provided that nothing in this Article shall be deemed to require any such person as aforesaid to sit and act as a Judge of that Court unless he consents so to do.
Mode of Appointment of Judge:
Article 124 (2) provides that every Judge of the Supreme Court shall be appointed by the President by warrant under his hand and seal after consultation with such of the Judges of the Supreme Court and of the High Courts in the States as the President may deem necessary for the purpose and shall hold office until he attains the age of sixty five years.
Provided that in the case of appointment of a Judge other than the Chief Justice, the Chief Justice of India shall always be consulted.
Till 1972, the post of the Chief Justice of India was filled on the basis of seniority of the existing Supreme Court Judges but it was broken in 1973 when Justice A.N. Roy was appointed the Chief Justice after superseding his three senior colleagues.
In 1977, Janata Party Government again brought the practice of seniority among the Supreme Court Judges, for appointment of the Chief Justice of India.
In the Judges Transfer Case AIR 1982 S.C. 149 Justice P.N. Bhagwati has suggested that there should be constituted a panel for suggesting the name of the Chief Justice of India, as the existing system in this regard is Inadequate.
Judicial supremacy in appointment of Supreme Court and High Court Judges:
In a historic Judgment in S.C. Advocate-on-Record Association v. Union of India, (1993) 4 S.C.C. 441, a nine Judge Bench of the Supreme Court by a 7-2 majority overruled its earlier Judgment in the Judges Transfer case (S.P. Gupta vs. Union of India) and held that in the matter of appointment of judges of the Supreme Court and the High Courts, the Chief Justice of India should have primacy.
The court held that the greatest significance should be attached to the view of the Chief Justice of India formed after taking into account the views of the two senior most judges of the Supreme Court. Qualification of a Judge
According to Article 124 (3), a person shall not be qualified for appointment as a Judge of the Supreme Court unless he is a citizen of India and:
(a) Has been for at least five years a Judge of a High Court or two or more such courts in succession, or
(b) Has been for at least ten years an advocate of a High Court or of two or more such courts in succession, or
(c) Is in the opinion of the President, a distinguished jurist.
Removal of a Judge:
According to Article 124(4), a judge of a Supreme Court shall not be removed from his office except by an order of the President passed after an address by each House of Parliament supported by a majority of the total membership of that House and by a majority of not less than two-thirds of the members of that House present and voting has been presented to the President in the same session of such removal on the ground of proved misbehavior or incapacity.
Article 124(5) provides that Parliament may by law regulate the procedure of the presentation of an address and for the investigation and proof of misbehavior or Incapacity of a judge under clause (4).
According to Article 124(6), every person appointed to be a judge of the Supreme Court shall, before he enters upon his office, make and subscribe before the President, or such other person appointed in this behalf by him, an oath or affirmation according to the form set out for the purpose in the Third Schedule for allegiance to the Constitution and faithful performance of duties without fear or favor.
No person who has held the office of a judge of the Supreme Court shall plead or act in any court or before an authority within the territory of India.