How the world’s largest democracy casts its ballots

About 600 million Indian citizens are expected to cast their votes over a period of 39 days ending May 19, in the ongoing election for their country’s parliament. There are roughly 900 million eligible voters, and the country has typically seen about two-thirds of them turn out to polling places.

I have been working on the security of electronic voting systems for more than 15 years, and, along with other colleagues, have been interested in understanding how a nation can tally that many votes cast over such a long period. India uses a domestically designed and manufactured electronic voting machine – as many as 4 million of them at 1 million polling places, at least some in extremely remote locations.

Different areas of India vote on seven different days, over the course of a 39-day election period. Furfur, translated by RaviC/Wikimedia Commons, CC BY-SA
The first version of the Indian electronic voting machine debuted in the state election in Kerala in 1982. Now they’re used in elections throughout the country, which happen on different days in different areas.

How does it work?

When a voter arrives at the polling place, she presents a photo ID and the poll officer checks that she is on the electoral roll. When it’s her turn to vote, a polling official uses an electronic voting machine’s control unit to unlock its balloting unit, ready to accept her vote.

The balloting unit has a very simple user interface: a series of buttons with candidate names and symbols. To vote, the voter simply presses the button next to the candidate of her choice.

After each button press, a printer prints out the voter’s choice on paper and displays it to the voter for a few seconds, so the person may verify that the vote was recorded correctly. Then the paper is dropped into a locked storage box.

The whole system runs on a battery, so it does not need to be plugged in.

When it’s time for the polling place to close at the end of the voting day, each electronic voting machine device and paper-record storage box is sealed with wax and tape bearing the signatures of representatives of the various candidates in that election, and stored under armed guard.

A woman tests an electronic voting machine in India in advance of that country’s national elections. AP Photo/Manish Swarup
After the election period is over and it’s time to tally the votes, the electronic voting machines are brought out, the seals opened and the vote counts for each control unit are read out from its display board. Election workers hand-tally these individual machine totals to obtain the election results for each constituency.

Security protections – and concerns

The Indian electronic voting machine primarily runs on specialized hardware and firmware, unlike the voting machines used in the U.S., which are software-intensive. It is intended for the single purpose of voting and specially designed for that, rather than relying on a standard operating system like Windows, which needs to be regularly updated to patch detected security vulnerabilities.