Nearly 50 million Americans are expected this fall to use touch-screen equipment. Many states and counties moved to electronic voting machines after the contested 2000 results in Florida.
"No matter how you cut this, voters are concerned about their votes being counted," said Rep. Juanita Millender McDonald (D., Calif.), a member of the House Administration Committee, which oversees voting systems.
"Given the gravity of the security failings the computer security community has documented . . . it is irresponsible to move forward without addressing them," said Avi Rubin, a professor at the Johns Hopkins University Information Security Institute in Baltimore. The institute's doctoral candidates found significant design and programming flaws in software for Diebold voting machines, a popular system.
The general problem, according to Rubin, is that there is no way for election officials to be sure that electronic machines are free of malicious code designed to manipulate results.
He said companies were reluctant to share their "source code," the proprietary software that controls voting and tabulating results, so that their software can be checked independently. "We need more public scrutiny," Rubin said.
On Tuesday, the U.S. Election Assistance Commission, founded in the aftermath of the 2000 vote to help states ensure fair elections, will try to come up with ways to reduce security vulnerabilities and make source codes available to independent testers.
Earlier this year, California Secretary of State Kevin Shelley banned the use of a Diebold system in some counties after determining that software problems jeopardized vote results.
Election officials dismissed the criticism yesterday from computer experts. "Although any electronic voting system is hypothetically 'hackable,' I am confident that the likelihood of this occurring is extraordinarily remote," said Linda Lamone, Maryland's election administrator.
Lamone outlined a dozen challenges a hacker would have to overcome. Chief among them: obtaining a working knowledge of the software's specific programming language and gaining physical access to computer servers and voting machines.
"There has not been one single case of election fraud due to tampering with a voting system's hardware or software," she said.
Election officials who use electronic machines also credited them with reducing the number of voters disenfranchised by previously used mechanical systems.
Computer experts worry that because most electronic voting machines lack a paper trail, it would be impossible to conduct an accurate recount in a contested election, Rubin said. He advocates a return to paper ballots as a backup.
The federal voting commission is looking into guidelines for paper verification.
Contact reporter Sumana Chatterjee at 202-383-6040 or email@example.com.