U.S. voters go to the polls on Tuesday, but already lawyers are lining up on both sides of the partisan fence, preparing to challenge this year's presidential election, should there be any "irregularities." One of the things they'll be paying close attention to is the system of so-called "electronic voting" that has become increasingly popular in the United States over the last four years. Many communities went high-tech after Florida's well-publicized problems with paper punch-card ballots in 2000. But as VOA's Maura Farrelly reports, some computer scientists say electronic voting this year could end up making the last presidential election look like an exercise in organization and efficiency.

There is no uniform voting system in the United States. Many places, like New York City, still use the old, heavy, but simple and reliable lever machines that first became popular in the nineteenth century. Other communities, some of them located in the battleground state of Ohio, are using the same punch card ballots that resulted in "hanging chads" in Florida four years ago. But an unprecedented number of American voters will be using computers when they go to the polls.

Thanks to the federal Help America Vote Act, which gave almost $4 billion to the states so they could update their voting infrastructure, about one third of Americans will be voting electronically. Many will be using touch screens designed by an Ohio-based company called Diebold. Company spokesperson David Bear says the computerized machines have advantages.

"Touch screen voting is much more accessible to voters with special needs," he says. "Someone who is blind can take a ballot completely unassisted, by having the ballot read to them [by the computer]. Someone who is sight impaired, they can change the font, so it's easier to read. Someone [for whom] English may not be a native language, it's much easier to adapt a ballot to meet their language needs."

The touch-screens also won't allow someone to "over vote." In Florida in 2000, many voters mistakenly punched out the names of two presidential candidates, and then dropped their ballots into the box. Those ballots were later declared invalid. But a computer won't let someone cast a vote like that. Instead, it will alert the voter to his mistake so he or she can fix it, and that's one of the many reasons touch-screen technology is being hailed by election officials in 30 states.

But not every official is embracing the technology. Reed Gusciora is a state assemblyman from New Jersey who's filed a lawsuit to block the use of more than 8,000 electronic voting machines in his state. So far, New Jersey hasn't had any problems with the touch-screens, but Mr. Gusciora says he's trying to prevent the difficulties voters in other states encountered during their primary elections earlier this year.

"There have been problems in California, where four counties have cancelled the use of them," he notes. "A jurisdiction in Pennsylvania, once you go down to the open-space question, the candidate switched to the other party. So as more and more of these anecdotes come across, there's been concern about whether electronic voting machines can guarantee the integrity of the election."

Reed Gusciora is concerned about the sort of programming glitches that affect computers all the time. But he says he'd be less concerned if the machines in his state provided a paper copy of each ballot. That way voters could review the document, to make sure the computer did what they wanted it to do and then drop the physical copy into a ballot box, where it could be retrieved and reviewed by officials, should there be any problems with the computer program. Right now, Nevada is the only state where touch screens that print written records for voters are being used. And that's a problem, says Will Doherty, executive director of verifiedvoting.org. It's a grassroots organization, made up primarily of computer scientists who think technology has a lot to offer the electoral system, but say the old-fashioned policy of keeping a "paper trail" shouldn't be abandoned.

"You know, this is common practice for any other important applications we have in our lives," he says. "If you look at the automated teller machines. [W]hen you go to a bank to get money from a bank machine, that machine prints not only a paper receipt for you, the customer, it also prints two paper receipts for the bank. They do that because the computer that's running that machine can crash, and they want to make sure they have a record of what happened, so they can figure out where the money should go. And I would submit to you that our votes are as important as our financial transactions with a bank."

So how likely is it that these machines will crash? Diebold and the other companies that make them insist they're very reliable, and they also say election officials can get a paper printout from each machine, after the election is over. But critics say anything that's printed out after the fact is useless, since it can't be verified by voters. And they say these machines are vulnerable to hacking. Dan Wallach is a Computer Science professor at Rice University who's examined the software designed by the Diebold company, which makes about 30 percent of the touch screens that will be used on November 2. Professor Wallach says the company's code encryption techniques are some of the simplest he's ever encountered.

"I teach software engineering to college students, so I look at software as something that I can give a grade to. And what we saw is that the Diebold source code is built very poorly," he says. "It's not up to any of the standards that you would expect for any kind of high reliability software. Software like this would never be allowed to fly an airplane, never be allowed to run a medical device. Even gambling machines-you know, Las Vegas slot machines-are built to better standards."

Dan Wallach says the machines wouldn't even have to be compromised by a hacker in order for the election's legitimacy to be questioned. A good hacker, after all, doesn't get caught. But if you know a computer system is vulnerable, you aren't going to trust it-regardless of whether you discover evidence that the system has, in fact, been tampered with. And if Americans don't trust the system they're being required to use on November 2, that could cause problems especially if the vote is close, as political experts expect it to be.