A computer science expert who has studied Georgia's outdated voting machines testified Thursday that inherent defects, age and “repeated security mistakes” by the state made the 2018 election “far more vulnerable than most other states and most other elections.”

A “telltale sign” that votes were tallied by defective machines used during the midterm election last November was a “significant undervote rate” in the lieutenant governor's race that was bolstered by anecdotal reports from voters who had difficulty casting a vote for that race, said Matthew Bernhard, a consultant on election security for plaintiffs in ongoing civil litigation contesting the validity of the election of Lt. Gov. Geoff Duncan.

A nonprofit election transparency group, a former candidate for secretary of state and several Georgia voters banded together to challenge Duncan's election by claiming “multiple unexplained failures” of the state's electronic voting machines skewed the race against Democrat Sarah Riggs Amico.

The lawsuit claims that reported statewide vote totals show people skipped voting for lieutenant governor more than any other race, including down-ballot races for attorney general and labor commissioner. The suit contends—and Bernhard testified Thursday—that the pattern was reflected only in votes cast on electronic voting machines but did not appear in paper absentee and provisional ballots.

The undervote appeared to have a greater impact on Amico than Duncan, the suit claims. Amico is not a party to the suit, although its claims are mirrored in a letter outlining her concerns she forwarded to the secretary of state shortly after the election.

Duncan beat Amico by 123,172 votes. Nearly 3.8 million votes were counted.

On Tuesday, Bernhard called the undervote “a statistically significant aberration.”

In one largely Democratic precinct with eight electronic voting machines, seven machines tallied Democrats winning every statewide race. A single machine tallied Republicans winning every race by approximately the same margin as Democrats on the other seven machines.

Because voters would choose voting machines randomly, all of the machines should have had similar tallies, he said.

“It's extremely unlikely that seven machines would show a regular pattern and one machine would be completely the opposite,” he said. “To me, it seems like a programming error.”

The vulnerabilities to hacking and defects in the machines themselves could only be confirmed by a forensic analyses of voting machines used during the Nov. 8 election, according to the plaintiffs. But an effort to review the internal memory of a cross-section of machines used in Fulton County failed, despite a court order from presiding Senior Superior Court Judge Adele Grubbs granting limited discovery.

Fulton election officials, on the advice of the secretary of state's general counsel, refused to provide Bernhard with the access he wanted to adequately inspect the machines.

Without an inspection of the electronic voting machines, the plaintiffs have no definitive proof to back up the statistical analyses of their experts. The electronic voting machines have no paper trail that would provide a means of showing whether the tallies were accurate.

On Jan. 9, Grubbs denied motions to dismiss the case and ordered limited discovery that included an inspection of machines in Fulton, Henry and Worth counties prior to trial Thursday. Fulton's refusal to allow Bernhard to conduct the inspection he needed in a way that he said would not alter or destroy the data on the voting machines prompted plaintiffs' counsel Bruce Brown to ask for a continuance and for a jury trial earlier this week. Brown also filed a motion to compel election officials to permit an inspection of the electronic voting machines' internal memory storage, which Grubbs had initially allowed.

Grubbs denied all of Brown's motions.

When Bryan Tyson, an attorney with Atlanta's Strickland Brockington Lewis who is representing Gwinnett election officials, challenged Bernhard's conclusions and sought to dismiss his testimony because he had not personally inspected the voting machines, Brown sought Bernhard's testimony that he had been barred from inspecting the machines in a manner that would not have altered the existing internal memory.

But Grubbs refused to let Bernhard testify, saying she had already denied Brown's motion to compel. Instead, Grubbs said that Bernhard and the plaintiffs were given an opportunity to inspect the machinery, just not what they wanted to inspect or in the way they wished to do so.

“You refused to take it,” she said. “You wanted to do it some other way. That issue is done.”

When Brown began to explain, saying, “If I may,” Grubbs exploded.

“Not, 'if you may,'” she said. “You always wonder 'if you may.' I've been through this over and over and over. You emailed me at 11 at night. You emailed me at 1 in the morning. I've looked at it. The question of discovery is done.”

Every time Brown attempted to elicit information about what needed to be done to prove whether any of the electronic voting machines had failed or otherwise been compromised, Grubbs—prompted by a chorus of objections from the defense—shut him down.

Duncan's counsel, Dentons partner Edward Lindsey, who was accompanied by his co-counsel, former Georgia Attorney General Sam Olens, persuaded Grubbs to strike the bulk of Bernhard's testimony.

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