Article 170 is a provision in the Constitution of India that deals with the Composition of the Legislative Assemblies (Vidhan Sabhas) of the States. It is a foundational constitutional article that outlines the structure of the state-level lower house of the legislature.
The article was adopted as Draft Article 149 on January 8, 1949, and was part of the original Constitution of India, which came into effect on January 26, 1950. It was created to ensure a democratic and population-based representation in the State Legislative Assemblies, thereby solving the problem of unequal representation.
Article 170(1) mandates that a State Legislative Assembly shall consist of not more than five hundred and not less than sixty members, chosen by direct election from territorial constituencies in the State. Article 170(2) requires that each State be divided into territorial constituencies so that the ratio between the population of each constituency and the number of seats allotted to it is, as far as practicable, the same throughout the State. This mechanism upholds the principle of "one person, one vote, one value". Article 170(3) requires that upon the completion of each census, the total number of seats and the division of the State into territorial constituencies shall be readjusted by an authority determined by Parliament. This process of redrawing boundaries is known as Delimitation.
This provision connects directly to the Delimitation Act, which Parliament enacts to determine the authority and manner of readjustment. It also relates to Article 82, which mandates a similar readjustment for Lok Sabha seats. The process is typically carried out by the independent Delimitation Commission.
Article 170 has been significantly amended to freeze the readjustment of seats. The 42nd Constitutional Amendment Act, 1976, froze the allocation of seats based on the 1971 census. The 84th Amendment Act, 2001, extended this freeze on the total number of seats until the first census taken after the year 2026. However, the 87th Amendment Act, 2003, permitted the readjustment of territorial constituencies within a State based on the 2001 census figures, without altering the total number of seats. The core principle of population-based representation remains, but the actual number of seats and their inter-state allocation has been frozen since 1976.