The Three Judges Cases are a series of three landmark Supreme Court judgments and an advisory opinion that fundamentally redefined the process of appointing and transferring judges to the higher judiciary in India, leading to the creation of the Collegium System. The cases arose from the interpretation of the word "consultation" in Article 124(2) and Article 217(1) of the Constitution, which govern the appointment of judges to the Supreme Court and High Courts, respectively.
The first case, S.P. Gupta v. Union of India (1981), held that "consultation" did not mean "concurrence," giving the Executive (Union Government) primacy in judicial appointments. This ruling was overturned by the second case, Supreme Court Advocates-on-Record Association v. Union of India (1993), which ruled that "consultation" must mean concurrence, thereby shifting primacy to the Judiciary and establishing the Collegium System. The ratio of the Second Judges Case was that the Chief Justice of India's (CJI) recommendation was binding on the President, but the CJI had to consult with their two senior-most colleagues.
The third case, In re Special Reference 1 of 1998, was an advisory opinion delivered under Article 143 of the Constitution, which clarified and expanded the Collegium System. The Supreme Court ruled that the CJI's recommendation for Supreme Court appointments must be made in consultation with a collegium of the four senior-most judges, not just two, and that the recommendation must be a collective decision. This mechanism, where the judiciary appoints its own members, is the current system, though it was recently challenged by the 99th Constitutional Amendment Act, 2014, which created the National Judicial Appointments Commission (NJAC). The Supreme Court struck down the NJAC in the Fourth Judges Case (2015), reaffirming the Collegium System established by the Three Judges Cases.