Punchscan with Independent Ballot Sheets: Simplifying Ballot Printing and Distribution with Independently Selected Ballot Halves

We propose and implement a modification to the Punchscan protocol that simplifies ballot printing and distribution. In this improved version, each voter creates a ballot at the polling location by combining independently selected ballot halves, rather than using two pre-selected halves with the same serial number. The only time a ballot used for voting is human-readable is when it is in the voter’s hands, reducing possible opportunities to violate voter privacy. This small but nontrivial change lets election officials print and distribute ballots using multiple printers more easily, without giving any one printer the ability to compromise voter privacy with certainty.