The Indian Constitution is a unique blend of rigidity and flexibility, allowing for amendments to adapt to changing societal needs while preserving its fundamental structure. Article 368 of Part XX of the Constitution outlines the procedure for its amendment. However, this power is not absolute and is subject to significant restrictions, primarily established by the Supreme Court.

Procedure for Amending the Constitution (Article 368):

Article 368 provides for two main methods of amendment, in addition to certain provisions that can be amended by a simple majority of Parliament (which are not considered amendments under Article 368 itself):

1. Amendment by Special Majority of Parliament:

   • An amendment bill can be introduced in either House of Parliament (Lok Sabha or Rajya Sabha), not in state legislatures.
   • It does not require prior recommendation of the President.
   • The bill must be passed in each House by a special majority, which means:
     • A majority of the total membership of that House (i.e., more than 50% of the total strength of the House).
     • A majority of not less than two-thirds of the members of that House present and voting.
   • Each House must pass the bill separately; there is no provision for a joint sitting in case of disagreement.
   • After being passed by both Houses, the bill is presented to the President, who must give his assent (made obligatory by the 24th Constitutional Amendment Act, 1971). The President cannot withhold assent or return the bill for reconsideration.
   • This method is used for amending most provisions of the Constitution, including Fundamental Rights and Directive Principles of State Policy.

2. Amendment by Special Majority of Parliament and Ratification by States:

   • This method is required for amending provisions related to the federal structure of the Constitution. These include:
     • Election of the President (Articles 54, 55).
     • Extent of the executive power of the Union and States (Articles 73, 162).
     • Supreme Court and High Courts (Chapter IV of Part V, Chapter V of Part VI).
     • Distribution of legislative powers between the Union and States (Chapter I of Part XI).
     • Any of the Lists in the Seventh Schedule.
     • Representation of States in Parliament (Fourth Schedule).
     • The power of Parliament to amend the Constitution itself (Article 368).
   • The procedure is the same as above (special majority in both Houses of Parliament), but with an additional requirement:
   • The amendment must also be ratified by the Legislatures of not less than one-half of the States by a simple majority (i.e., a majority of the members present and voting).
   • There is no time limit within which the states must ratify the amendment.

Restrictions on Amending Power: The Basic Structure Doctrine

The most significant restriction on Parliament's amending power is the 'Basic Structure Doctrine,' propounded by the Supreme Court. This doctrine holds that Parliament cannot amend those provisions of the Constitution which form its 'basic structure' or 'essential features.'

1. Kesavananda Bharati v. State of Kerala (1973): This landmark judgment established the Basic Structure Doctrine. The Supreme Court, by a 7:6 majority, held that while Parliament has the power to amend any part of the Constitution, including Fundamental Rights, this power is not unlimited. It cannot be used to alter, abrogate, or destroy the 'basic structure' or 'fundamental features' of the Constitution. The Court, however, did not provide an exhaustive list of what constitutes the basic structure, leaving it to future judicial determination. Some elements identified or implied include:

   • Supremacy of the Constitution
   • Republican and Democratic form of Government
   • Secular character of the Constitution
   • Separation of powers between the legislature, executive, and judiciary
   • Federal character of the Constitution
   • Judicial review
   • Freedom and dignity of the individual
   • Parliamentary system
   • Rule of law

2. Indira Nehru Gandhi v. Raj Narain (1975): The Supreme Court applied the Basic Structure Doctrine and struck down Clause (4) of Article 329A, which was inserted by the 39th Amendment, as it violated the basic structure of the Constitution (e.g., free and fair elections, rule of law, judicial review).

3. Minerva Mills v. Union of India (1980): This case further strengthened the Basic Structure Doctrine. The Court struck down two provisions of the 42nd Amendment Act, 1976, which had given absolute primacy to Directive Principles over Fundamental Rights and removed judicial review of constitutional amendments. The Court held that the limited power of Parliament to amend the Constitution is itself a basic feature, and the harmony and balance between Fundamental Rights and Directive Principles is also a part of the basic structure.

4. Waman Rao v. Union of India (1981): The Court clarified that the Basic Structure Doctrine would apply to constitutional amendments enacted after April 24, 1973 (the date of the Kesavananda Bharati judgment). Amendments made before this date were not subject to this doctrine.

In conclusion, while Article 368 provides a clear procedure for amending the Constitution, the power is not unfettered. The Supreme Court, through the Basic Structure Doctrine, has imposed a crucial substantive restriction, ensuring that the core identity and foundational principles of the Indian Constitution remain inviolable. This judicial innovation maintains the balance between the need for constitutional evolution and the preservation of its fundamental ethos.