Article 81 (3) is a crucial provision in the Constitution of India that defines the term "population" for the purpose of determining the composition of the House of the People (Lok Sabha). The provision states that "population" means the population as ascertained at the last preceding census of which the relevant figures have been published. This definition is fundamental to the principle of population-based representation outlined in Article 81 (2), which mandates that the ratio of seats allotted to a State to its population must be, as far as practicable, the same for all States.
The original intent was to re-adjust the number of seats and constituency boundaries after every census, a process known as delimitation. However, this mechanism was altered to address concerns that States successfully implementing family planning policies would be penalised with fewer Lok Sabha seats. Consequently, the 42nd Amendment Act, 1976, introduced a freeze on the use of the latest census data.
This provision has been significantly amended to postpone the full re-adjustment of seats. The current proviso to Article 81 (3), as amended by the 84th Amendment Act, 2001, and the 87th Amendment Act, 2003, specifies a dual standard. For the allotment of seats to States (Article 81 (2)(a)), the population figures of the 1971 census are used. For the purpose of re-adjusting the boundaries of territorial constituencies within a State (Article 81 (2)(b)), the figures of the 2001 census are used. This constitutional freeze is set to continue until the relevant figures for the first census taken after the year 2026 have been published.