I believe there was an MIT study done after the contentious 2000 US election that compared election methods and their error rates. None had a zero error rate.

I believe there was an MIT study done after the contentious 2000 US election that compared election methods and their error rates. None had a zero error rate. Fully electronic was not preferable because of the lack of audit trail. The best system seemed to be paper with scanners. The error rate was among the lowest and it is fully auditable. After this study came out I was disappointed that my state chose fully electronic. But before this last election we went to paper with scanners. The big advantage of course is the ability to recount by hand to your heart’s content. Which of course we did.