Constitutional Law of India
The Constitution of India lays down the framework on which Indian polity is run. The Constitution declares India to be a sovereign socialist democratic republic, assuring its citizens of justice, equality, and liberty. It was passed by the Constituent Assembly of India on November 26, 1949, and came into effect on January 26, 1950. India celebrates January 26 each year as Republic Day. It is the longest written constitution of any independent nation in the world, containing 395 articles and 12 schedules, as well as numerous amendments, for a total of 117,369 words in the English language version. Besides the English version, there is an official Hindi translation.

The Constitution lays down the basic structure of government under which the people chose themselves to be governed. It establishes the main organs of government - the executive , the legislature and the judiciary. The Constitution not only defines the powers of each organ, but also demarcates their responsibilities. It regulates the relationship between the different organs and between the government and the people.
The Constitution is superior to all other laws of the country. Every law enacted by the government has to be in conformity with the Constitution. The Constitution lays down the national goals of India - Democracy, Socialism and National Integration. It also spells out the Fundamental Rights, Directive Principles and Duties of citizens.

Features:
The Constitution of India draws extensively from Western legal traditions in its enunciation of the principles of liberal democracy. It is distinguished from many Western constitutions, however, in its elaboration of principles reflecting aspirations to end the inequities of traditional social relations and enhance the social welfare of the population. According to constitutional scholar Granville Austin, probably no other nation's constitution "has provided so much impetus toward changing and rebuilding society for the common good." Since its enactment, the constitution has fostered a steady concentration of power in the hands of the central government - especially the Office of the Prime Minister. This centralization has occurred in the face of the increasing assertiveness of an array of ethnic and caste groups across Indian society. Increasingly, the government has responded to the resulting tensions by resorting to the formidable array of authoritarian powers provided by the Constitution. However, a new assertiveness shown by the Supreme Court and the Election Commission suggests that the remaining checks and balances among the country's political institutions are resilient and capable of supporting Indian democracy. Furthermore regional parties are gaining popularity at the expense of national parties which has led to coalition governments at the centre. As a consequence, power is becoming more decentralised.

The Constitution in its final form owes much to a number of different principles from various other Constitutions. The general structure of the Constitution's democratic framework was largely the work of B. N. Rau, a constitutional scholar of international standing. Supporters of independent India's founding father, Mohandas K. Gandhi, backed measures that would form a decentralized polity with strong local government — known as panchayat — in a system known as Panchayati Raj, i.e. rule by Panchayats. However, the view of more modernist leaders such as Jawaharlal Nehru, ultimately prevailed leading to the establishment of a parliamentary system of government and a federal system with a strong central government