India, June 23 -- Imagine a family reunion after sixteen years, where everyone has changed. Some cousins have had five kids, others have chosen to have just one, and some have moved to big cities, while others have stayed in their ancestral villages. Now imagine trying to decide how to split inheritance and voting rights fairly among everyone. That is essentially what India faces with Census 2027, except the "family" is 1.4 billion people, and the stakes are the future of the world's largest democracy.

The government's announcement that Census 2027 will begin with a March 1st reference date has sent ripples through political corridors from Kerala to Kashmir. After sixteen years-the longest gap since Independence-this is not just a routin...