Optical-scan machines made by Election Systems & Software failed recent pre-election tests in a Michigan county, producing different tallies for the same ballots every time, the top election official in Oakland County revealed in a letter made public Monday.

The problems occurred during logic and accuracy tests in the run-up to this year's general election, Oakland County Clerk Ruth Johnson disclosed in a letter submitted October 24 (.pdf) to the federal Election Assistance Commission (EAC). The machines at issue are ES&S M-100 optical-scan machines, which read and tally election results from paper ballots.

Johnson worried that such problems – linked tentatively to paper dust build-up in the machines – could affect the integrity of the general election this week.

"The same ballots, run through the same machines, yielded different results each time," she wrote. "This begs the question – on

Election Day, will the record number of ballots going through the remaining tabulators leave even more build-up on the sensors, affecting machines that tested just fine initially? Could this additional build-up on voting tabulators that have not had any preventative maintenance skew vote totals? My understanding is that the problem could occur and election workers would have no inkling that ballots are being misread."

Tuesday's election is expected to be the busiest ever, and ES&S tabulators – both touchscreen machines and optical-scan machines – were responsible for counting 50 percent of the votes in the last four major U.S. elections, according to the company. The company's optical-scan machines are now deployed in 43

states.

Johnson, who could not be reached for comment, said that "four of our communities or eight percent" had reported inconsistent vote totals during the logic and accuracy tests with the ES&S machines. She also said that conflicting vote totals had surfaced in other areas of

Michigan as well, though she didn't elaborate on this in her letter.

"While problems with performance and design with the M-100s have been documented, this is the first time I have ever questioned the integrity of these machines," Johnson wrote in her letter.

According to news stories, a race in the August Republican primary in one Michigan township did have a discrepancy in tallies that were counted by hand and by ES&S optical-scan machines. The clerks race in Plymouth Township was recounted after the losing candidate requested it. The initial machine count had showed Joe Bridgman defeating Mary

Ann Prchlik by 1,920 to 1,770. But the hand count narrowed the margin to 1,885 to 1,727. Officials attributed the discrepancy to "smears and marks" on the ballots, which skewed the results when they were run through the machines.

In Oakland county when officials there met with ES&S to discuss the errors encountered during logic and accuracy testing, ES&S

maintained that the problem was dust and debris build-up on the sensors inside the machines.

"This has impacted the Digital to Analog Converter (DAC) settings for the two Contact Image Sensors (CIS)," Johnson wrote the EAC.

Johnson also revealed in the letter that county officials are prohibited from performing maintenance or cleaning on the machines or they risk voiding ES&S warranties. ES&S has not performed any preventative maintenance on the machines since they were delivered three years ago.

Johnson closed her letter by urging the Commission to investigate whether vote totals could be affected by the failure to perform regular cleaning and preventative maintenance on the machines. She requested a

"federal directive or law" that would allow county clerks to conduct random audits to test machine accuracy using machines that have had preventative maintenance performed in the last year. She also urged officials to develop a plan for accurately canvassing election results.

"I believe this matter, which is not a partisan issue, but an issue of integrity, needs your immediate attention and I would urge you to investigate as so much is at stake," she wrote.

ES&S has not responded to a call for comment. [Update: ES&S has disputed Johnson's claim in an e-mail sent to Threat Level. The company said Johnson misrepresented the issue and that the problem was operator error that, once corrected, resulted in accurate vote totals.]

The Election Assistance Commission, which quietly posted the letter to its web site today, did not send an announcement about the issue to election officials but simply included a link to the letter in a routine newsletter that it distributed by e-mail to election officials shortly before 5 pm Eastern time, less than 24 hours before voters around the country arrive to the polls.

EAC spokeswoman Jeannie Layson said the Commission received Johnson's letter late in the afternoon on Wednesday after EAC chairwoman Rosemary

Rodriguez, to whom the letter was addressed, had left to conduct an interview with ABC's 20/20 program. She said Rodriguez was out of the office Thursday and Friday and only saw the letter today when she returned.

John Gideon, co-executive director of Voters Unite, an election integrity group, said he was troubled by the Commission's lack of urgency over the matter.

"If they haven't done anything with it then how are they fulfilling their duties as a clearinghouse and passing on information?" he asked.

"If they didn't do something with it, as far as I'm concerned it's misfeasance. They have a legal duty to warn election officials of problems."

Gideon said it was particularly troubling, because there was likely an easy fix to the problem if the issue was related to build-up in the machines.

He pointed to a problem that occurred in 2004 in Yakima County,

Washington, with optical-scan machines made by Hart InterCivic. During a hand recount of the governor's race in the general election, election officials discovered that machines had failed to count votes on 24

ballots. An investigation later revealed that the machine had missed the votes (.pdf) due to "a small foreign object (dirt or paper debris) in the scanner."

An e-mail sent from Hart InterCivic to officials concluded that

"periodic cleaning of scanners during periods of heavy use will reduce the risk" of losing votes and that a service representative could provide them with proper training and supplies to clean the machines.

The Election Assistance Commission was created by the Help America Vote

Act of 2002 to serve as a clearinghouse of election administration information and to oversee the federal testing and certification of voting machines, but it has yet to certify any voting system under its testing program, which was launched in early 2007.

The Commission has often been criticized by voting activists for failing to monitor problems with voting machines and share crucial information that election officials need to have.

Layson told Threat Level in September that since the Commission didn't oversee the certification of any voting systems that are currently being used in elections, it has no official role in monitoring the equipment and will only monitor voting equipment problems that occur with systems that become certified under its program.

Pamela Smith, president of Verified Voting, said the important thing with regard to the ES&S scanners is that voters get assurance that their votes will be counted accurately.

"When significant problems such as this one are discovered by diligent officials like the one who reported this case, remedies must be developed," she wrote Threat Level in an e-mail. "At the very least, the EAC could proactively alert other jurisdictions using this type of voting system that it may be an issue. That way, states that are willing to conduct post-election audits could do so, and check their vote counts."

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