University of Trento
In this paper, the authors present new insights into central properties of voting systems, namely verifiability, privacy, and coercion-resistance. They demonstrate that the combinations of the two forms of verifiability considered in the literature - individual and universal verifiability - are, unlike commonly believed, insufficient to guarantee overall verifiability. They also demonstrate that the relationship between coercion-resistance and privacy is more subtle than suggested in the literature. Their findings are partly based on a case study of prominent voting systems, threeBallot and VAV, for which, among others, they show that, unlike commonly believed, they do not provide any reasonable level of verifiability, even though they satisfy individual and universal verifiability.