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Working Knowledge: Voting Machines—Competing Candidates

Taking apart the various voting machines used in the U.S.

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Whenever national elections occur, debates arise over which voting technology is most accurate and least susceptible to tampering. The arguments have been waged ever since mechanical machines arrived more than a century ago as an alternative to paper ballots.

Lever machines dominated U.S. polling places from the 1930s through the 1980s but are now used only in New York State, having been gradually replaced by optical scanners and touch screens. The scanners are similar to equipment used to score standardized tests. Touch screens, known as direct recording electronic (DRE) machines, operate somewhat like ATMs.

View Voting Machines Around the U.S.


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Various studies have reached disparate conclusions about which technologies more accurately count votes and which are hardest to hack, although voter mistakes are lower for DREs. New York State asserts that lever machines are as good as other technologies, but some experts disagree. A review by California, which uses a mix of options, found none to be clearly superior. Even though lab tests have shown differences, “when you factor in real-world variables, like ease of use and proper administration by poll workers, accuracy ends up being similar”—about one error in 10,000 votes, says Douglas W. Jones, a computer science professor at the University of Iowa and an expert on voting technology.

Better ballot design could also reduce mistakes. “We’ve been designing hard-to-use ballots since this country began, and that’s not about to change,” Jones quips. The latest worry is about tampering with DREs. Before polls open, workers insert a flash memory card into each machine to set the ballots. A virus impregnated in the cards could alter the recording of results, a scheme demonstrated by Edward W. Felten, a computer science professor at Princeton University. Only one allegation of tampering has been brought to court, however, and investigations showed that the odd voting pattern was because of bad ballot design.

Increasing spending on elections could improve security, accuracy and ballot design. But jurisdictions try to run elections on the cheap, Jones says, so machine makers operate on thin margins and there is little money for testing.

Did You Know ... ABSENT: For most absentee ballots, voters fill in ovals on a page and mail it to
their county election center. High-speed optical scanners that can count 10 ballots
a second process the returns. The scanners reject problematic ballots, which are supposed to be adjudicated by a resolutions board but sometimes just get ignored, according to Douglas W. Jones of the University of Iowa. It is not uncommon for 4 to 10 percent of absentee ballots to go uncounted.

ONLINE: Internet voting is increasingly used for company shareholders’ meetings, but it is rare in politics. Estonia, the Netherlands and Geneva, Switzerland, have tried it for general elections, and Okaloosa County, Florida, is promoting a pilot project for the race this November. But until security can be ensured—a tall order—most computer scientists say states should not commit.

View Voting Machines Around the U.S.

Note: This article was originally printed with the title, "Competing Candidates".

Mark Fischetti was a senior editor at Scientific American for nearly 20 years and covered sustainability issues, including climate, environment, energy, and more. He assigned and edited feature articles and news by journalists and scientists and also wrote in those formats. He was founding managing editor of two spin-off magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 article “Drowning New Orleans” predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. Fischetti has written as a freelancer for the New York Times, Sports Illustrated, Smithsonian and many other outlets. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti has a physics degree and has twice served as Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union’s Robert C. Cowen Award for Sustained Achievement in Science Journalism. He has appeared on NBC’s Meet the Press, CNN, the History Channel, NPR News and many radio stations.

More by Mark Fischetti
Scientific American Magazine Vol 299 Issue 4This article was published with the title “How Voting Machines Work” in Scientific American Magazine Vol. 299 No. 4 ()
doi:10.1038/scientificamerican102008-39WFd5NACrt1T1m90CHWrZ

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