ES&S Voting Machines Can Be Maliciously Calibrated to Favor Specific Candidates
"If one candidate has a check box in one place and a different candidate has it in a different place, you can set it up so that if you press on one candidate it gets recorded for another candidate," said Matt Blaze, a computer scientist at the University of Pennsylvania who led one of three teams that co-wrote the report (.pdf) last year. "But if you press on the other candidate, it gets recorded correctly for that candidate. You can make it work perfectly normally in most of the screen, but have it behave the way you want in small parts of it."
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