A look inside the electronic voting machine

March 10, 2018 10:43 pm | Updated December 04, 2021 10:44 pm IST

The ELCs will familiarise students with EVMs and VVPAT. File Photo

The ELCs will familiarise students with EVMs and VVPAT. File Photo

Can the EVM be rigged or tampered with? We look at the technical and institutional safeguards that the Election Commission claims are in place to prevent electoral malpractice.

Addressing common concerns

Is it technically possible to manipulate the EVM? A look at some frequently raised concerns Can EVMs be hacked?

Unlike voting machines in some countries which are connected to a network, Indian EVMs are standalone. Tampering an EVM through the hardware port or through a Wi-Fi connection is not possible as there is no frequency receiver or wireless decoder in the EVM machine.  What if the chip inside the EVM is replaced or a Bluetooth device is inserted within the EVM?

This would mean that the institutional safeguards to protect the EVM (sealing and hardware checks, among others) are breached to fit a device within the EVM and to manipulate it from outside. In M3 machines, this is also technologically ruled out, as they shut down in the event of tampering.


Can EVMs be manipulated by chip manufacturers?

The EVMs are produced indigenously by two PSUs - Bharat Electronics Ltd. and Electronics Corporation of India Ltd. - where the software programme for the chip is written and converted into machine code before being given to the microchip manufacturer. The chips with digital signatures are subjected to functional tests on the embedded software. EVMs are randomly assigned to polling booths across States and candidates are alphabetically listed on ballot sheets (inserted onto the EVM’s ballot unit). For EVMs to be manipulated at the manufacturing level, it is assumed that there is some trojan present in the EVM already that will lead to votes being transferred to a particular party. This is impossible as there is no prior way in which the order of the candidate can be known besides the location where the EVMs will be used. In addition, VVPAT machines now display the voter’s choice, thereby bringing an extra layer of verification.   Why do we need an EVM over simple ballot paper?

EVMs have had several advantages over ballot paper - the foremost being the elimination of invalid votes. A statistical exercise by The Hindu found that in more than 300 of the 36,000-odd seats where elections were held over the years, invalid votes were significant enough to have affected the mandate. The EVM has rendered the invalid vote moot. A paper by Brookings India also found that EVMs reduced electoral fraud and re-polling due to electoral rigging, and made elections a safe affair, thereby enhancing voter turnout.


Checks and balances

The EVMs pass through many hoops before being placed in front of a voter. A brief look at the steps involved 1. Functional check: The machines are cleaned and earlier results are cleared. Switches, buttons, cables and latches are inspected for damage  2. Trial run: A mock poll is conducted. One vote is cast against each of the 16 candidate buttons. If VVPATs are used, six votes are polled for every candidate button. Results are verified 3. Random check: Another mock poll is conducted on 5% of the total number of EVMs to be used for a poll. About 1,000 votes are polled and the result printouts are shared with representatives of various political parties  4. Throwing the dice: Two rounds of randomisation take place. During the first, EVMs are allocated at random to a constituency. In the second round, they are randomised and allocated to a polling booth


5. Candidate listing: The candidate list with symbol, name and party of the candidate is inserted into the ballot paper screen and the ballot unit is closed  6. Connecting the devices: The ballot unit is connected to the control unit. The control unit is opened and the ‘candidate set’ button is pressed. Then the last candidate button on the balloting unit is pressed. This indicates that the EVM will have only this many candidates 7. A dry run: Before the start of the actual poll, a mock poll is conducted with at least 50 votes in the presence of candidates or their agents. The mock poll is then closed and the results are displayed 8. Final checks: On poll day, various checks are conducted by polling agents, observers and central paramilitary forces 9. End notes: The poll is closed by pressing the ‘close’ button on the control unit. The total number of votes polled is noted. Serial numbers of the seals used are also noted 10. Safe and secure: EVMs are placed in their carrying cases and sealed. The machines are transported back to the reception centres under armed escort and kept in the strong room.

Evolution of the machine

With each iteration, new security features and in-built mechanisms have been incorporated. A look at the three models M1 Manufactured: 1989-2006 Last used: 2014 general elections Not compatible with VVPAT M2 Manufactured: 2006-2012 In use Encryption, time-stamping of key press M3 Manufactured: 2013 onwards In use; 9 lakh more will replace older models by end of 2018 Stops functioning if tampered with and has self-diagnostics.



Text: Varun B. Krishnan, Vignesh Radhakrishnan, Srinivasan Ramani

Illustration and graphic: Kannan Sundar

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