Are Barcodes on Ballots Bad? Decoding Ballot Marking Device Security
Kevin Skoglund decodes 1D and 2D barcodes on ballot-marking devices (ES&S, Dominion, Unisyn), evaluating the security risks of machine-readable votes.
Summary
The Proliferation of Ballot Marking Devices (BMDs)
Many U.S. election jurisdictions utilize touchscreen Ballot Marking Devices (BMDs) that print paper ballots containing both human-readable text and computer-readable barcodes.
Reverse Engineering Ballot Barcode Formats
Kevin Skoglund breaks down the proprietary 1D and 2D barcode schemas used across leading voting systems (ES&S ExpressVote, Dominion ImageCastX, and Unisyn OpenElect).
The Critical Security Flaw of Barcode Tallying
Skoglund explains that because optical scanners tally the barcode rather than the human-verified printed text, malicious malware could alter barcode data without voter detection.
Recommendations for Verifiable Paper Ballots
The author advocates for hand-marked paper ballots and optical character recognition (OCR) scanning to ensure votes counted match human intent.
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