An optical scan vote counting system developed by David Chaum to provide a voter-verifiable, end-to-end audit mechanism. The order of candidates on the ballot is generated pseudo- randomly. The ballot itself consists of two layers of paper. The top layer lists the candidates with symbols beside their names; the bottom layer has the symbols only. The top sheet is performed so that it is possible for the voter to mark both the top and bottom sheets simultaneously with an ink marker. Having done so, the voter chooses either as a receipt and destroys the other. The receipt is tabulated at the polling place after which the voter is free to take it home. The receipt itself does not have enough information to allow the voter to prove how she voted. The scanner is able to interpret the ballot because it is able to reference a database with information indicating the correspondence between voting positions and candidates. The scanned ballots can be posted online so that each voter can be sure that her ballot formed part of the final tally.
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An optical scan vote counting system developed by David Chaum to provide a voter-verifiable, end-to-end audit mechanism. The order of candidates on the ballot is generated pseudo- randomly. The ballot itself consists of two layers of paper. The top layer lists the candidates with symbols beside their names; the bottom layer has the symbols only. The top sheet is performed so that it is possible for the voter to mark both the top and bottom sheets simultaneously with an ink marker. Having done so, the voter chooses either as a receipt and destroys the other. The receipt is tabulated at the polling place after which the voter is free to take it home. The receipt itself does not have enough information to allow the voter to prove how she voted. The scanner is able to interpret the ballot because it is able to reference a database with information indicating the correspondence between voting positions and candidates. The scanned ballots can be posted online so that each voter can be sure that her ballot formed part of the final tally.
Cite this term
Election Security Glossary. (2026). Punchscan. In Election Security Glossary. Retrieved August 13, 2026, from https://electionsecurityglossary.com/glossary/punchscan
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