"Basic Structure" consists of those essential pillars of the constitution which are considered as vital to its very existence, and which Parliament cannot amend or take away even by a constitutional amendment. The word "Basic Structure" is not mentioned in constitution, but was recognized for the first time in the historic Kesavananda Bharati case of 1973.  The list of Basic structure includes supremacy of the constitution, judicial review, federalism, independence of judiciary etc.

           The constitution under Article 368 empowers the Parliament to amend the constitution, but this power is not absolute.  With the intention of preserving the original ideals envisioned by the constitution makers, the Supreme Court pronounced that Parliament could not distort or alter the basic features of the Constitution under the pretext of amending it.  If the Supreme Court finds any law made by the Parliament inconsistent with the constitution, it has the power to declare that law to be invalid (Article 13 and 14). Ever since the Kesavananda Bharati case, Supreme Court has been the interpreter of the Constitution and the arbiter of all amendments made by Parliament.

Evolution of the Basic Structure

The evolution of Basic Structure doctrine can be traced from issue of right to property and first constitutional amendment bill 1951 itself.

• The First Constitution Amendment Act, 1951 was challenged in the Shankari Prasad vs. Union of India. But the Supreme Court held that the Parliament, under Article 368, has the power to amend any part of the constitution including fundamental rights.
  
  
• In Golak Nath vs State of Punjab case in 1967, the Supreme Court overturned Shankari Prasad judgement and ruled that Article 368 only lays down the procedure to amend the constitution and does not give absolute powers to the Parliament to amend any part of the constitution.
  
  
• To nullify Golak Nath judgement, the Parliament, in 1971, passed the 24th Constitution Amendment Act and gave the absolute power to Parliament to make any changes in the constitution including the fundamental rights.
  
  
• In 1973, in Kesavananda Bharti vs. State of Kerala case, the Supreme Court held that the Parliament has power to amend any provision of the constitution, but doing so, the basic structure of the constitution is to be maintained.
  
  
• Further in Minerva mills and Waman Rao cases, SC reaffirmed its position of Kesavananda Bharti judgment and mentioned that the basic structure doctrine is applicable post 1973.
  
  

Despite the larger number of amendments made to the Indian Constitution, the hopes and ideas of its framers remain intact and identifiable as the Constitution adopted in 1949. This is principally due to the Supreme Court’s decision in Kesavananda Bharati.