SUPREME COURT IN 1973 IN KESAVANANDA BHARATI VS. STATE OF KERALA

As to what are these basic features, the debate still continues. The Supreme Court has also held that the scope of certain fundamental rights could be adjudged by reading into them or reading them not only in the light of the Directive Principles of State Policy but also international covenants or conventions which were in harmony with the Fundamental Rights.
The Fundamental Rights — embodied in Part III of the constitution — guarantee civil liberties such that all Indians can lead their lives in peace as citizens of India. The six fundamental rights are right to equality, right to freedom, right against exploitation, right to freedom of religion, cultural and educational rights and right to constitutional remedies. These include individual rights common to most liberal democracies, incorporated in the fundamental law of the land and are enforceable in a court of law. Violations of these rights result in punishments as prescribed in the Indian Penal Code, subject to discretion of the judiciary. These rights are neither absolute nor immune from constitutional amendments. They have been aimed at overturning the inequalities of pre-independence social practices. Specifically, they resulted in abolishment of untouchability and prohibit discrimination on the grounds of religion, race, caste, sex, or place of birth. They forbid human trafficking and unfree labour. They protect cultural and educational rights of ethnic and religious minorities by allowing them to preserve their languages and administer their own educational institutions.

All people, irrespective of race, religion, caste or sex, have the right to approach the High Courts or the Supreme Court for the enforcement of their fundamental rights. It is not necessary that the aggrieved party has to be the one to do so. In public interest, anyone can initiate litigation in the court on their behalf. This is known as "Public interest litigation". High Court and Supreme Court judges can also act on their own on the basis of media reports. Fundamental Rights primarily protect individuals from any arbitrary State actions, but some rights are enforceable against private individuals too. For instance, the constitution abolishes untouchability and prohibits begar. These provisions act as a check both on State action and actions of private individuals. Fundamental Rights are not absolute and are subject to reasonable restrictions as necessary for the protection of national interest.
In the Kesavananda Bharati vs. state of Kerala case, the Supreme Court ruled that all provisions of the constitution, including Fundamental Rights can be amended. However, the Parliament cannot alter the basic structure of the constitution like secularism, democracy, federalism, separation of powers. Often called the "Basic structure doctrine", this decision is widely regarded as an important part of Indian history.
In the 1978 Maneka Gandhi v. Union of India case, the Supreme Court extended the doctrine's importance as superior to any parliamentary legislation. According to the verdict, no act of parliament can be considered a law if it violated the basic structure of the constitution. This landmark guarantee of Fundamental Rights was regarded as a unique example of judicial independence in preserving the sanctity of Fundamental Rights. The Fundamental Rights can only be altered by a constitutional amendment, hence their inclusion is a check not only on the executive branch, but also on the Parliament and state legislatures. The imposition of a state of emergency may lead to a temporary suspension of the rights conferred by Article 19 (including freedoms of speech, assembly and movement, etc.) to preserve national security and public order. The President can, by order, suspend the right to constitutional remedies as well.