Engineering Practical End-To-End Verifiable Voting Systems

Dr. Richard Carback
Charles Stark Draper Laboratories


We designed, built, tested, and fielded a vote counting system called Scantegrity. Scantegrity is part of a new class of end-to-end (E2E) verifiable voting systems that are designed to solve chain of custody problems in elections by providing a privacy-preserving receipt to each voter. The voter can use the receipt to check a public record and verify that his or her ballot is counted without revealing the selected candidate. The public record gives election officials the ability to provide a strong, universally-accessible audit of the results, enabling transparent, verifiable elections that maintain privacy expectations. E2E verifiable voting systems offer radical improvements to integrity and transparency of election systems, and the adoption of these systems in public-sector elections can improve outcome integrity. In this talk, we explain how Scantegrity works and examine the balance between usability and security concerns. We further examine the implementation through the results of a field test of Scantegrity from the Takoma Park, Maryland, November 2009 municipal election, where we were able to survey voters and observe events throughout Election Day.