Which judicial principle limits the absolute protection originally sought by the Ninth Schedule of the Constitution? 

The limitation on the Ninth Schedule’s immunity flows from the basic structure doctrine, first articulated in Kesavananda Bharati v. State of Kerala (1973). While Parliament possesses wide amending power under Article 368, the Supreme Court held that this power cannot be exercised to destroy or damage the Constitution’s basic features, such as judicial review, rule of law, equality, democracy, and separation of powers. Although the Ninth Schedule was initially designed to shield laws from Part III challenges, later jurisprudence clarified that it cannot operate as a constitutional “black hole.” This position was conclusively affirmed in I.R. Coelho v. State of Tamil Nadu (2007), where the Court held that laws placed in the Ninth Schedule are subject to basic-structure review. Thus, constitutional supremacy prevails over legislative devices.