The President's power to appoint judges has been laid down under Article 124(2). However, the appointing power has certain restrictions from within the article itself. The President is required to 'consult' the judges of Supreme Court, and of the High Courts, as he may deem necessary. The first proviso to Article 124 has also required the President to consult with the Chief Justice of India while appointing other judges.
The word 'Consultation' in Article 124 has been interpreted by the Supreme Court in various case laws.
In S.P. Gupta v. Union of India, 1981 Supp SCC 87 (First Judges Case), it was held that 'consultation' in Article 124 means 'mere consultation of views' and not 'concurrence of views'. Therefore, the Court said that the President was not bound by the opinion of the Chief Justice.
In Supreme Court Advocates-on-Record Assn. v. Union of India, (1993) 4 SCC 441 (Second Judges Case), overruled S.P Gupta v. Union of India, and held that in matters of appointment of Judges, the opinion of the Collegium has primacy, therefore, 'consultation' means 'concurrence of views'. The President is bound by the views of the Collegium.
The Collegium system was introduced by the Supreme Court in the Second Judges Case, it is a system of appointment and transfer of judges. It is a five-member body, comprising of the Chief Justice and four Senior most Judges of the Supreme Court.