Receipt-Free, Universally and Individually Verifiable Poll Attendance
Nicholas Akinyokun, Vanessa Teague · Proceedings of the Australasian Computer Science Week Multiconference · 2019
We examine cryptographic techniques for protecting voters from coercion not to vote in pollsite elections. Although many other works have evaluated the receipt-freeness of the ballots cast by voters, very few have considered the privacy issues arising from whether the voter attended the polling place at all. Our objectives are simple: to simultaneously protect against voter coercion and ballot stuffing. In our voter attendance verification scheme, any voter can verify whether their attendance has been counted (which indicates whether they voted or not), and any third party can verify the total number of voters that attended any given polling place on election day. To mitigate voter coercion, impersonation and disenffanchisement, our scheme requires the look-up of a public web bulletin board, but it does not require complex voter verification -- we simply expect the voters to check the consistency of the 1-bit secret integer that was assigned to them during registration. We prove the receipt-freeness property of our scheme to ensure that a voter (or a registered non-voter) when challenged by an adversary, can always produce a transcript that indicates either that they have attended, or if they prefer, that they have not attended their assigned polling place to vote.