The Doctrine of Basic Structure is a principle developed by the Supreme Court of India which states that while Parliament has the power to amend the Constitution, it cannot alter or destroy its basic features. This doctrine was established in the Kesavananda Bharati case in 1973. Elements like the supremacy of the Constitution, rule of law, separation of powers, judicial review, and fundamental rights are considered part of the basic structure and cannot be taken away even by a constitutional amendment.

The Doctrine of Basic Structure is a judicial principle in Indian constitutional law that holds certain fundamental features of the Constitution are inviolable and cannot be altered or destroyed by amendments made by Parliament—even under its broad amending powers in Article 368.

Origin and Evolution
The doctrine was established by the Supreme Court in the landmark Kesavananda Bharati v. State of Kerala (1973) case. The Court ruled by a narrow majority that while Parliament has wide powers to amend the Constitution, it cannot change its "basic structure" or essential features.

This principle was not explicitly mentioned in the Constitution but was evolved by the judiciary to preserve the spirit and foundational values of the Constitution against arbitrary or radical changes by the legislature.

Key Components of the Basic Structure
Although the Supreme Court did not provide an exhaustive list, over time, several features have been recognized as forming the basic structure, including:

Supremacy of the Constitution

Rule of law

Separation of powers among the legislature, executive, and judiciary

Judicial review

Federalism

Secularism

Sovereign, democratic, and republican nature of government

Free and fair elections

Independence of the judiciary

Unity and integrity of the nation

Welfare state

Parliamentary system

Harmony and balance between Fundamental Rights and Directive Principles

Significance
The doctrine acts as a safeguard against arbitrary or excessive constitutional amendments, ensuring that the core values and identity of the Constitution remain intact.

It empowers the judiciary, particularly the Supreme Court, to review and strike down constitutional amendments that violate or alter the basic structure.

This principle preserves the nature of Indian democracy, protects citizens' rights and liberties, and maintains constitutional stability.

Examples of Application
In the Indira Nehru Gandhi v. Raj Narain (1975) and S.R. Bommai v. Union of India (1994) cases, the Supreme Court invoked the doctrine to strike down amendments or actions that threatened the Constitution’s core features.

The doctrine has been used to uphold the independence of the judiciary, the rule of law, and the federal structure of India.

Conclusion
The Doctrine of Basic Structure is a unique and vital judicial innovation that ensures Parliament’s power to amend the Constitution is not absolute. It protects the Constitution’s foundational principles, thereby maintaining the vision of its framers and the democratic ethos of the nation