Prêt á voter with write-ins

This paper presents an extension of the Pret a Voter verifiable voting system to handle write-ins. This is achieved by introducing an additional 'Write-In' option and allowing the voter optionally to enter a write-in candidate of their choice. The voter obtains a receipt which includes their write-in, but that receipt does not indicate whether the write-in candidate was selected or not. The system provides flexibility with respect to the tallying of write-in votes. We also introduce null ballots in order to achieve receipt-freeness with respect to write-ins.