The Supreme Court of India was tasked with reviewing the constitutionality of sub-classification within the Scheduled Castes (SC) for reservation purposes. Specifically, the Court revisited the principles established in the 2004 judgment of E.V. Chinnaiah v. State of Andhra Pradesh, which had ruled against sub-classification within SCs. In EV Chinnaiah, the Supreme Court had held that all the castes in the Presidential Order under Article 341(1) of the Constitution formed one class of homogeneous group and the same could not be further subdivided. This matter was referred to a 7-judge bench to resolve whether states could create separate quotas for more backward sub-groups within the SC category.

• 1. Whether sub-classification within the SC category for the purpose of reservations is permissible under the Indian Constitution.
• 2. The validity of the E.V. Chinnaiah judgment, which had previously declared that SCs form a homogeneous group and cannot be subdivided further for reservation purposes.

• • Majority Opinion: Chief Justice DY Chandrachud, writing for himself and Justice Misra, noted that SCs are not a homogeneous group and that sub-classification does not violate Articles 14 or 341 of the Constitution. The Court emphasized that while states can implement sub-classification, it must be justified with empirical data, and reservations cannot be allocated 100% to any sub-class.
• • Concurring Opinions: Justice Gavai, Justice Nath, Justice Mithal, and Justice Sharma supported the view that states have a duty to offer preferential treatment to more backward SC groups and that the "creamy layer" principle should apply to SCs as well. Justice Gavai specifically highlighted the need to exclude more advantaged individuals within SCs from affirmative action benefits.
• • Dissenting Opinion: Justice Trivedi dissented, arguing that sub-classification amounts to altering the Presidential list of SCs, which should only be modified by Parliament. Her ladyship contended that sub-classification could lead to unequal benefits among different SC sub-groups and is beyond the states' legislative powers.

• • The Supreme Court, by a majority of 6-1, overruled the E.V. Chinnaiah judgment, allowing for the sub-classification of SCs to grant separate quotas within the SC category.
• • The Court recognised the power of the State to identify and provide distinct quotas for more backward sub-groups within SCs, provided the State justifies the same on the basis of empirical data that a sub-class in whose favour such more beneficial treatment is provided is not adequately represented.
• • However, while providing for sub-classification, the State would not be entitled to reserve 100% seats available for Scheduled Castes in favour of a sub-class to the exclusion of other castes in the list and that such a sub-classification would be permissible only if there is a reservation for a sub-class as well as the larger class.
• • The ruling highlights that while sub-classification is permissible; it must be carefully justified and cannot result in exclusive reservations for any single sub-class.