Bihar votes big: Did SIR actually boost voter turnout?

THe number one stage of polling in 121 come out of the 243 assemblage constituencies (AC) in Bihar is at present done. According to the voter turnout data released by the Election Commission of India (ECI) as of 8:30 p.m. On Thursday, the voter turnout in all these ACs combined is 64.66%.This number is 9.3 and 8.8 percentage points higher than the turnout in these ACs in the 2024 Lok Sabha or 2020 assembly elections, respectively, and in fact the highest in any state or national election in Bihar since the 2010 state election, the earliest period for which we have comparable AC boundaries and AC-level turnout data.To be sure, the impressive increase in voter turnout numbers should not be taken at face value. This is because Bihar’s electoral roll experienced a significant decline following the special intensive revision (SIR) exercise conducted by the ECI.Also Read | Never let rioters, criminals taste power: Yogi Adityanath in BiharWhile the state saw a net deletion of 3.07 million electors between the electoral rolls as of the 2024 Lok Sabha and the final roll after the SIR, entailing a 4% reduction in the total elector count, the 121 ACs which went to polls on Thursday saw a deletion of 1.53 million voters or 3.9% compared to the 2024 Lok Sabha. However, there is another important statistic from the latest turnout data.ECI had listed the total number of registered electors for these 121 ACs at 37.51 million, 0.4% more than the 37.37 million count in the final SIR roll. This means that 24.3 million electors have cast their vote in today’s phase of polling. This number exceeds 21.55 million electors who voted in these ACs in the 2024 Lok Sabha elections.The biggest takeaway from this comparison is that the process of SIR of the electoral roll in Bihar has not led to an absolute decline in the number of voters. This can be seen in another way by examining the growth in electors and voters in assembly elections, which have been held exactly five years apart since 2010.Also Read | Caste equations, welfare schemes shape Bihar’s poll moodBetween the 2010 and 2015 assembly elections, the number of electors increased by 21.7% in these 121 ACs, and the number of voters increased by 30.5%. Between the 2015 and 2020 elections, the number of electors and voters increased at roughly the same pace: 9.2% and 9.5%, respectively.In the 2025 election, voter turnout increased by 17.1%, a rate between the earlier growth rates, although the number of electors increased by only 1.1%. This means that the number of voters increased at a rate similar to that seen previously, despite the growth in electors slowing down.This lends theoretical support to the logic that the SIR did not weed out a significant number of actual voters on the ground, and the deletions were largely confined to voters who migrated or were registered in more than one place and therefore overwhelmingly populated the ranks of voters who did not vote even in the past.Also Read | Bihar deputy CM Vijay Sinha blames ‘goons of RJD’ as his convoy is attacked on polling dayHT had listed this as a possibility in its analysis of the draft SIR electoral roll data released on August 1. Of course, this cannot be ascertained with certainty, because ECI does not publish a list detailing the identities of electors who turned out to vote. It is also true that Bihar’s voter turnout has been among the lowest among major states, suggesting that many persons on the pre-SIR rolls may not have been active voters.