A 2016 HBO documentary, Hacking Democracy, discusses voting irregularities and the ease of hacking the results of electronic voting systems:
It introduces Bev Harris, a 52 year old grandmother who stumbled upon evidence of vote tampering. She went on to create Black Box Voting, a nonpartisan investigative reporting and public education organization for elections.
Apparently these Diebold machines employ a Windows NT operating system. Here’s an excerpt from a Security Analysis of the Diebold AccuVote-TS Voting Machine: “Simply put, many computer scientists doubt that paperless DREs [Direct Recording Electronic voting systems] can be made reliable and secure, and they expect that any failures of such systems would likely go undetected.”
Despite these problems, we believe that it is possible, at reasonable cost, to build a DRE-based voting system—including hardware, software, and election procedures—that is suitably secure and reliable. Such a system would require not only a voting machine designed with more care and attention to security, but also an array of safeguards, including a well-designed voter-verifiable paper audit trail system, random audits and forensic analyses, and truly independent security review.
It’s much easier to audit a paper ballot system. Computers are faster than paper, but, to at least some degree, vulnerable to hacking.