Why is Mamata Banerjee scared of SIR in Bengal, and vocal against action on illegal immigrants? Research paper says there may be 1 crore+ excess voters in her state

The Special Intensive Revision of the electoral roll in poll-bound Bihar has opened a Pandora’s box, exposing how illegal voters backed by forged documents and political patronage have infested Indian democracy. The Election Commission of India uncovered over 60 lakh unverified voters during the SIR exercise in Bihar. However, the opposition parties have stirred a political storm, claiming that the SIR exercise is a ‘conspiracy’ to disenfranchise a specific group of voters, especially Muslims.

First, RJD and Congress opposed the SIR exercise and raised questions over the integrity of the ECI, claiming that it is functioning at the behest of the BJP. Now, they are crying hoarse over the SIR findings as well as the nationwide crackdown on illegal Bangladeshi immigrants.

Notably, a research paper by professors from the prestigious IIM institutions had already cautioned about the same and indicated that there are more than 70 lakh bogus voters in Bihar.

Interestingly, the drive disclosed that 35 lakh people were either untraceable or had permanently relocated, 22 lakhs were labelled as deceased, and 7 lakh voters were enrolled in multiple locations, while about 1.2 lakh forms are pending.

What started as ECI’s efforts to weed out fake voters from the electoral roll in Bihar has renewed the vigour of the ongoing anti-illegal immigrant campaign across several states.

Predictably, the drive to detect, detain and deport illegal Bangladeshi and Rohingya Muslim immigrants has anguished the ‘secular’ political parties in the country.

Mamata Banerjee ‘reminds’ BLOs that they work for the state government, not the ECI

Amidst a crackdown on illegal immigrants in Haryana and other states (BJP ruled) and the SIR in Bihar, West Bengal Chief Minister Mamata Banerjee, whose government has been accused of aiding illegal infiltration to increase its vote bank, has opened a front against the BJP.

CM Banerjee, who once vowed to never allow implementation of the NRC in West Bengal, has repeatedly been attacking the Modi government over the detention of suspected Bangladeshi and Rohingya illegals, claiming that they are Bengali migrants.

The West Bengal Chief Minister has ‘reminded’ the Booth Level Officers (BLOs), who are presently undergoing training for summary revision by the Election Commission of India, that they work for the state government and not the ECI. She said authoritatively that the names of voters should not be excluded from the electoral process arbitrarily.

Addressing an administrative meeting in Birbhum in July this year, CM Banerjee said, “The ECI takes over only after the poll dates are announced. Until then, and even after that, the administration lies with the state government. You are employees of the state government. Do not harass any individual needlessly.”

Her supposed ‘reminder’ for BLOs came across more as a threat. Further casting aspersions on the integrity of the Election Commission and accusing the body functioning at the behest of the BJP, Banerjee said, “The (voters’) list is being prepared by people sitting in Gujarat. An agency of the BJP is doing this. I know its name. You will see chhau dance (a tribal dance) and face the music of drums and conch shells if you dare to strike off names from the voters’ list in Bengal. I won’t allow the NRC to be implemented and set up detention camps till I am alive.”

West Bengal is the state with the highest number of illegal Bangladeshi immigrants living with forged documents and local help

Apparently, the Trinamool Congress supremo fears that if and when a Special Intensive Revision is conducted in West Bengal, lakhs of fake voters, especially illegal immigrants who have obtained forged documents, would be weeded out. It is not a secret that West Bengal is among the states with the highest numbers of illegal Bangladeshi immigrants. In the last three years, 2688 Bangladeshi nationals were apprehended and sent back to Bangladesh.

On 8th August, the TMC government sought a ‘clarification’ from West Bengal Chief Election Officer (CEO) over reportedly writing to the Election Commission of India that the state is “ready” to undergo the SIR exercise. Last week, the ECI published the 2002 SIR voters’ lists for 293 Assembly Constituencies (ACs) except one. 

Notably, the last SIR in West Bengal occurred in 2002, forming the foundation for the 2004 electoral roll. It is, thus, highly likely that an SIR will be conducted in West Bengal later this year. It is notable here that updating the electoral roll and crossing out mistakes, deceased persons, and other discrepancies is one of the basic duties of the Election Commission.

While a ‘secular’ government (read Muslim-appeasing) in West Bengal is already ‘reminding’, ‘threatening’ and is outraged over the possible SIR exercise in the state, electoral roll inflation in the politically and communally charged state is real.

Research paper by IIM professors finds 1 crore excess voters in the 2024 West Bengal electoral roll

The findings of a research paper tiled: “Electoral Roll Inflation in West Bengal: A Demographic Reconstruction of Legitimate Voter Counts (2024)”; authored by Dr. Milan Kumar, Assistant Professor at the Indian Institute of Management Visakhapatnam and Dr. Vidhu Shekhar, Assistant Professor at SP Jain Institute of Management & Research, an alumnus of IIT Kharagpur and IIM Calcutta, reveal that the 2024 electoral roll of West Bengal may include approximately one crore excess voters, recording an inflation of whopping 13.69%.

The research paper published on 7^th August 2025, relies on official data from electoral rolls, census, and civil registration systems, to estimate the surviving voters from the 2004 base roll, additions through new cohorts (1986-2006 births), and adjustments for net permanent migration. The researchers employed a conservative methodology at each stage.

“We assume full registration among all eligible youth, apply high survival probabilities, and model migration based on decadal trends rather than recent acceleration. This allows us to generate a lower-bound estimate of the legitimate voter population. We then compare this figure to the official electoral roll published by the ECI for 2024,” the research paper states.

Highlighting its central finding that West Bengal’s 2024 voter list may contain more than one crore excess entries, representing a 13.69% inflation over the estimated legitimate electorate, the IIM professors raised concerns that such massive discrepancy, and its potential to affect electoral outcomes in a highly competitive state, “the implications for electoral integrity are significant.”

The research presents the empirical estimates of the legitimate voter population in West Bengal as of 2024, in three stages: (i) estimation of survivors from the 2004 roll, (ii) additions from new voter cohorts born between 1986 and 2006, and (iii) adjustments for net permanent migration. The researchers then synthesised the results to compute the estimated surplus in the electoral roll.

The 2004 electoral roll recorded 4.74 crore registered voters. The research disaggregated this population into six age groups and applied age-specific 20-year survival rates, using Census 2001 data. These projections yield an estimated 3.74 crore surviving voters from the 2004 roll.

Further, the researchers estimated that approximately 3.01 crore newly eligible individuals would have enrolled between 2004 and 2024.

The research then proceeded to estimate permanent outmigration and in-migration using Census 2001 and 2011 data. The analysis found that West Bengal experienced a decline in the absolute number of immigrants between 2001 and 2011.

Using Census 2001 and 2011 data and extrapolating via CAGR, the researchers estimated net permanent outmigration from West Bengal to be 17.86 lakh individuals during this period.

The researchers then combined all components to synthesise the data and to arrive at the final estimate of the legitimate voter population in West Bengal in 2024. The number of 2004 Registered Voters stood at 4,74,37,431. Deceased from 2004 cohort -1,00,37,743. The number of New Voters (1986–2006) is 3,00,93,512. Meanwhile, Net Migration estimates stood at -17,86,350.

The analysis states that the estimated number of legitimate voters (2024) is 6,57,06,849, while the number of voters per the official electoral roll (2024) is 7,61,24,780. This marks an estimated surplus of 1,04,17,931 voters, which in percentage translates into 13.69%.

The research emphasises that its final findings are a lower-bound estimate and the actual inflation may be significantly higher.

“These results imply that approximately 1.04 crore names, or 13.69% of the 2024 electoral roll, may not correspond to legitimately registered resident voters in the state. As noted throughout, our assumptions deliberately overestimate the legitimate count, suggesting that actual roll inflation may be even higher,” the research paper reads.

It further points out that a massive surplus of over 1 crore names raises questions over the credibility of electoral administration in the Trinamool Congress-ruled West Bengal. The report stresses that the scale of over-registration exceeds the margin of victory in numerous constituencies and “creates scope for fraud, impersonation, and political manipulation.”

“The study suggests an urgent need for tighter integration of electoral data with civil registration databases, Aadhaar, and interstate migration records. Algorithmic checks for implausible entries, such as centenarian clusters or multi-located registrations, coupled with quarterly demographic audits, could significantly improve roll accuracy and restore voter confidence,” the research paper reads.

The research also recommends an urgent Special Intensive Revision in West Bengal and other states, which have not had one in the last two decades, saying that a fresh SIR would enable door-to-door verification, linkages with death records, and targeted purging of inflated pockets at the constituency level.

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