The 42nd Amendment Act was enacted during the emergency period of 1976 by the government of India & then prime minister Indira Gandhi . Due to several important changes in “42nd Amendment Act’’ this is also called the “ Constitution Act ” . Often referred to as a mini constitution. So, this Amendment Act was one of the important Amendments of the constitution.
This AA affected the basic structure of the constitution.
It has also changed the balance of power between central and state government. And affected the federal nature of the state. And the federal structure of the constitution. By :
Amendment in preamble of constitution , added three words, socialist, secular , and integrity
And from the 7 th schedule of constitution , five state list subjects transferred into concurrent list subjects. Which were education, forest, protection of wild animals and birds , administration of justice & weight and measures. And Which affected the federal structure of India.
Of art. 368 of the constitution, increased parliament’s power to amend the constitution over state legislature and immune from judicial review. Which is an attempt to dominate the power of the state legislature on constitution amendment power.
The President can make law during an emergency without the consent of the state legislature.
Give priority to the DPSPs over fundamental rights.

Conclusion:-
Due to its very crucial amendments in the constitution of laws related to state and state subjects it is often criticised as central government attempts to create an egalitarian and totalitarian society. And affecting the federal structure of India and increasing Central rule over state. But after the end of emergency further Amendment 43rd and 44th Amendment Acts were done and modified the emergency constitution.