1. Supreme Court's judgement in the Golak Nath case (1967) by enacting the 24th Amendment Act (1971). This Act amended Articles 13 and 368. It declared that the Parliament has the power to abridge or take away any of the Fundamental Rights under Article 368 and such an act will not be a law under the meaning of Article 13.
2. However, in the Kesavananda Bharati case(1973), the Supreme Court Overruled its judgement in the Golak Nath case (1967). It upheld the validity of the 24th Amendment Act (1971) and stated that Parliament is empowered to abridge or take away any of the Fundamental Rights. At the same time, it laid down a new doctrine of the 'basic structure' (or 'basic features') of the Constitution. It ruled that the constituent power of Parliament under Article 368 does not enable it to alter the basic structure’ of the Constitution. This means that the Parliament cannot abridge or take away a Fundamental Right that forms a part of the basic structure' of the Constitution.
3. ‘Basic structure’ by enacting the 42nd Amendment Act (1976). This Act amended Article 368 and declared that there is no limitation on the constituent power of Parliament and no amendment can be questioned in any court on any ground including that of the contravention of any of the Fundamental Rights.
4. However, the Supreme Court in the Minerva Mills case (1980) invalidated this provision as it excluded judicial review which is a 'basic feature’ of the Constitution. Applying the doctrine of 'basic structure’ with respect to Article 368, the court held that;
5. “ Again in the Waman Rao case (1981), the Supreme Court adhered to the doctrine of the basic structure' and further clarified that it would apply to constitutional amendments enacted after April 24, 1973
ELEMENTS OF THE BASIC STRUCTURE
The following have emerged as 'basic features’ of the Constitution or elements / components / ingredients of the ‘basic structure’ of the constitution:
1. Supremacy of the Constitution
2. Sovereign, democratic and republican nature of the Indian polity
3. Secular character of the Constitution
4. Separation oi powers between the legislature, the executive and the judiciary
5. Federal character of the Constitution
6. Unity and integrity of the nation
7. Welfare state (socio-economic justice)
8. Judicial review
9. Freedom and dignity of the individual
10. Parliamentary system
11. Rule of law
12. Harmony and balance between Fundamental Rights and Directive Principles
13. Principle of equality
14. Free and fair elections