Kesavananda Bharati v. State of Kerala

The background

Swami Kesavananda Bharati, head of a Hindu mutt in Kerala, challenged state land-reform laws that restricted the management of religious property. The case quickly grew into the biggest constitutional question of the era: how far can Parliament go in amending the Constitution? After earlier rulings and a wave of amendments seeking to override fundamental rights, a record 13-judge bench was assembled to settle it.

The decision

By a wafer-thin 7-6 majority, the Supreme Court held that Parliament has wide power to amend any part of the Constitution, including fundamental rights - but it cannot alter or destroy the 'basic structure' or essential framework of the Constitution. Features such as the supremacy of the Constitution, rule of law, separation of powers, judicial review, federalism, and secularism are beyond the amending power.

What it changed

The judgment created the Basic Structure doctrine, the single most important check on Parliament's power in India. Courts have since used it to strike down constitutional amendments that threaten the Constitution's core. It permanently shifted the balance between Parliament and the judiciary and remains the bedrock of Indian constitutional law.