The Ninth Schedule of the Constitution initially shielded laws from Article 14/19/31 challenges. In
I.R. Coelho (2007), the Supreme Court held:

In I.R. Coelho v. State of Tamil Nadu (2007), the Supreme Court conclusively settled the controversy surrounding the Ninth Schedule. The Court held that all laws placed in the Ninth Schedule, irrespective of their date of insertion, are subject to basic structure review. The cut-off date of 24 April 1973 (the date of Kesavananda Bharati) determines the intensity of scrutiny, not immunity. The judgment emphasized that judicial review, equality, and rule of law are basic features of the Constitution. Parliament cannot use the Ninth Schedule as a device to validate laws that would otherwise violate these core principles. This decision reaffirmed constitutional supremacy over parliamentary majorities.