"That was a red flag for us, because when we started this project, we all felt that electronic voting was the solution," said Stephen Ansolabehere, an MIT (Massachusetts Institute of Technology) political science professor and former director of the project.
"We were shocked to see that ... electronic voting was not performing as well as hand-counted paper or optically scanned paper," he said.
A series of failures in primary and local elections across the nation further eroded the confidence in the technology. A report commissioned by the state of Maryland found that the electronic voting system showed a high risk of compromise.
"There is no way to know that a fully electronic voting system is actually going to record the results the way people voted them," said Avi Rubin, a computer-security researcher at Johns Hopkins University in Baltimore, Maryland.
The machine manufacturers say they have fixed the problems.
But one of the problems, critics say, is that the software code that runs the machines is proprietary, and therefore not open to public scrutiny.
Much of the problem has focused on the lack of a voter-verifiable paper trail. Most touch screen machines will not produce a receipt for the voters.
"This makes the job of a person who wants to cheat a lot easier," Rubin said. "If the machines had a paper trail, anyone could inspect the outcome, because the paper would give you the right answer."
Nevada will be the only state to use machines with reel-to-reel paper cartridges that voters can review. The machines were used for the fall primary, and tests later showed that the paper totals and electronic totals matched perfectly.
In California, Secretary of State Kevin Shelley required counties to use machines that could produce a paper record. But most counties had already bought their equipment, at a cost of U.S. $3,000 each. There are 5,000 voting precincts in Los Angeles County alone, each using six to seven machines.
Defenders of the paperless machines argue that they are easier to adapt for blind voters because they can be outfitted with audio units. There is also no risk of receipts jamming machines.
"While people have real concerns about electronic voting machines, there are also lots of benefits to this technology," said Jonathan Katz, a political science professor at Caltech University in Pasadena, California, and a member of the Caltech-MIT Voting Project. "We don't have to worry about hanging chads. If someone overvotes or undervotes, that person will be alerted electronically."
The greatest threat in electronic voting may actually come from people rather than machines. The average age of poll workers is reportedly close to 70. No matter how good the equipment is, those people have to make it work.
"Poll workers used to be observers, now they're service providers," said Ansolabehere, the MIT professor. "They're supposed to educate people on how to vote and intervene if there's a problem with a machine. There are more demands on poll workers than there used to be, and that's causing stress in the system."
Computer scientists say they fear a close election in which the results will be called into question.
"Where people are voting electronically, we won't be able to go back to accurately perform a recount of the voters' original intent," said Kohno of the University of San Diego.
But if that happens, he says, the polling station should be treated like a crime scene and computer security experts called in. "You want to preserve the forensics," Kohno said.
The bottom line: Come tomorrow, we may be longing for the days of the hanging chad.
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