Can Voters Detect Errors on Their Printed Ballots? Absolutely

There is still debate on whether voters can detect malicious changes in their printed ballot after making their selections on a Ballot Marking Device (BMD). In this study, we altered votes on a voter's ballot after they had made their selections on a BMD. We then required them to examine their ballots for any changes from the slate they used to vote. Overall accuracy was exceptionally high. Participants saw 1440 total contests, and of those 1440, there were a total of 4 errors, so total accuracy was 99.8%. Participants were able to perform with near-perfect accuracy regardless of ballot length, ballot type, number of altered races, and location of altered races. Detection performance was extremely robust. We conclude that with proper direction and resources, voters can be near-perfect detectors of ballot changes on printed paper ballots after voting with a BMD. This finding has significant implications for the voting community as BMD use continues to grow. Research should now focus on identifying administrative and behavioral methods that will prompt and encourage voters to check their BMD-generated ballots before they drop them in the ballot box.