Key Terms & Concepts — UPSC Mains
Constitution (131st Amendment) Bill — Lok Sabha Expansion
"The proposed constitutional amendment to expand Lok Sabha from 543 to 850 seats based on 2011 Census data — reigniting the North-South federal equity debate and its linkage to Women's Reservation implementation"
The Constitution (131st Amendment) Bill proposes to expand Lok Sabha from 543 to 850 seats by amending Article 81 of the Constitution. The expansion uses 2011 Census data (the last published Census, since the 2021 Census remains unpublished) as the population basis for seat allocation. Since the amendment changes representation of states in Parliament — a provision affecting India's federal structure — it requires a special majority in each House of Parliament (more than 50% of total membership AND two-thirds of members present and voting) AND ratification by at least half of all state legislatures, under Article 368(2). The Bill is accompanied by a separate Delimitation Bill to reconstitute constituency boundaries. Critics — particularly from southern states (Tamil Nadu, Kerala, Telangana, Karnataka, Andhra Pradesh) — argue that using 2011 population data rewards northern states that did not achieve the same population control success, effectively penalising southern demographic achievement.
High-priority UPSC GS-2 topic (Polity — constitutional amendments, federal structure, delimitation, Article 81/82/368). Prelims tests the amendment number (131st), the new seat count (850), the Census used (2011), and the required procedure (special majority + state ratification). Mains questions address the North-South federal equity debate, the TFR-population divergence between states, and the interlocking of Lok Sabha expansion with Women's Reservation Act implementation.
- 1 131st Amendment Bill — expands Lok Sabha from 543 to 850 seats (amends Article 81)
- 2 Uses 2011 Census data — the last published Census; 2021 Census unpublished as of 2026
- 3 Procedure — special majority in each House PLUS ratification by at least half of state legislatures (Article 368)
- 4 Accompanied by a Delimitation Bill to redraw constituency boundaries
- 5 North-South equity concern — northern states (UP, Bihar, MP) gain; southern states fear proportional loss
- 6 Linked to Women's Reservation Act 2023 — 33% reservation becomes operative only after delimitation
- 7 Historical context — 84th Amendment (2001) froze seat numbers; 42nd Amendment (1976) froze on 1971 Census basis
- 8 TFR divergence — Kerala TFR ~1.8 vs Bihar ~3.0; population-proportional seats punish demographic success
Tamil Nadu has repeatedly argued that state legislatures from southern states may refuse ratification of the 131st Amendment — invoking the constitutional requirement that at least half of all state legislatures must ratify federal-structure amendments — potentially blocking the expansion even if Parliament approves it.
