A national spotlight fell on Texas’ voting equipment last week after some voters complained that their votes on electronic voting machines had changed.

State election officials chalked it up to user error.

Critics alleged malfeasance or a software bug.

The Austin-based company behind the machines says an important piece of context is missing from this debate: these machines are 16 years old.

โ€œItโ€™s very much like someone calling Apple and asking for support on their iPhone 1,โ€ said Steven Sockwell, vice president of marketing at Hart InterCivic.

Most Texas counties last upgraded their electronic voting machines well over a decade ago, tapping billions in funds Congress approved to upgrade voting equipment around the country following election irregularities during the 2000 presidential election. Dozens of Texas counties purchased Hart’s eSlate machines.

It’s those same machines that a number of voters attempted to cast straight-ticket ballots on last week only to hit a snag: when they reviewed their list of candidates on the summary screen, their choices were deselected or a candidate from an opposing party was selected.

In a statement released last week, the secretary of stateโ€™s office said that the machines were not malfunctioning and that the issue, which affected fewer than 20 Texas voters, stemmed from voters โ€œtaking an action on the machine before it has finished rendering all the choices resulting from the voterโ€™s straight-party choice.โ€

โ€œWhat the secretary of state characterizes as user error, I characterize as a software bug,โ€ said Dan Wallach, a computer science professor at Rice University who studies electronic voting systems.

While he said he cannot know for sure why some votes were changed, he suspects that a bug known as a โ€œrace conditionโ€ could be to blame. A race condition is a common problem in computer science in which the machine must process two requests at the same time, and the dueling requests compete for the machineโ€™s resources, Wallach said.

โ€œIn software engineering, dealing with the case where there is more than one thing happening at the same time is the hardest type of software,โ€ Wallach said.

Records from the secretary of stateโ€™s office, which certifies election systems purchased by counties, show that the most recent certification of new eSlate software was in 2009. With software that is now about a decade old, Wallach said he would โ€œnot be surprisedโ€ if there is a bug.

Hovav Shacham, a computer science professor at the University of Texas at Austin who has previously reviewed the source code of Hart machines for Californiaโ€™s secretary of state, said he did not know if the voting issue last week was a bug or โ€œsome sort of surprising user interface quirk,โ€ but he stressed that the machine, and not the user, is at fault.

โ€œI think itโ€™s important that you donโ€™t get to blame a user for misbehavior of a machine,โ€ Shacham said. โ€œIf users are surprised at the end of their voter machine, thatโ€™s the machine.โ€

But Sockwell, with Hart, said there is no evidence of any design flaw in the eSlate voting machine.

โ€œThis is 2002 technology, and a half a second is longer than weโ€™re used to waiting because weโ€™re used to using 2018 technology,โ€ Stockwell said. โ€œBut I think the secretary of stateโ€™s explanation of what may be happening in terms of voters needing to slow down and check their answers is the right answer.โ€

Sam Taylor, the communications director at the Texas Secretary of State, also refuted allegations that there was any eSlate software glitch.

โ€œIf Mr. Wallach was correct that it is a software glitch, there would be many, many more reports of this occurring to voters,โ€ Taylor said. โ€œAnd it would have happened on a much larger scale over multiple elections.โ€

Similar problems did arise in 2016, according to the secretary of stateโ€™s statement. During that election, the secretary of state provided signs to election officials at polling locations that reminded voters to review their summary screens before casting their ballots.

Eight years earlier, the Texas Democratic Party sued then-Secretary of State Roger Williams over problems some voters were facing with straight-ticket voting, according to the Austin Chronicle. The lawsuit argued that those voting problems amounted to violations of the equal protection clause of the 14th Amendment as well as state and federal law. A U.S. district judge sided with Williams, and the U.S. 5th Circuit Court of Appeals upheld that ruling

John Oldham, the elections administrator for Fort Bend County in the Houston area, said he first became aware of the current straight-ticket voting issue with eSlate machines six years ago. He agreed that the problem arises from user error and not a machine issue.

โ€œEven though itโ€™s unfortunate that it is happening, itโ€™s the voter doing it,โ€ Oldham said. โ€œIf you put your cursor on straight Democrat, and maybe you double strike it, or it doesnโ€™t move fast enough, the cursor could have already moved down the page before you saw it.โ€

โ€œNormally, computers donโ€™t last that longโ€

While Sockwell said that the eSlate machines โ€œhave not been performing any differentlyโ€ than they have in previous elections, he said it is time for municipalities to upgrade to Hartโ€™s newer voter system, which is called Verity. The eSlate machines generally have a lifespan of between 10 and 15 years, he said, though he added that they do not stop working after 15 years.

Wallach said that he is surprised that Texasโ€™ eSlate machines have lasted as long as they have.

โ€œWeโ€™ve got eSlates that are over 10 years old and in some cases approaching 20 years,โ€ Wallach said. โ€œNormally, computers donโ€™t last that long.โ€

But election equipment is expensive, and there is not enough federal funding for the state to give to counties to replace all machines statewide, according to Taylor. A standard eSlate machine with a booth, instruction placards and a battery pack costs $2,200, according to Hart’s online catalog. The Verity system comes in a number of different configurations that range in price between $4,000 and $4,500, though Sockwell said counties sometimes negotiate lower prices. Taylor said that the state received about $23 million in federal funding in March in connection with the Help America Vote Act.

โ€œWhat we received this year does not even scratch the surface of what we would need to replace machines on a statewide basis or even in the top three Texas counties โ€“ which we estimate would cost upwards of $50 million for just Harris, Dallas, and Tarrant counties,โ€ Taylor said.

Taylor said the last time the state received โ€œa substantial amountโ€ to dole out to counties for the purchase of new machines was 2003.

Currently, eSlate machines are used in 82 of Texasโ€™ 254 counties. Around 7.2 million registered voters live in those counties, which account for 46 percent of registered voters in the entire state. And three of the five counties with the most registered voters, Harris, Tarrant and Travis, use them.

Travis County, which currently uses Hart voting machines, recently took the rare step of spending local money to upgrade their voting machines, signing an $8.16 million contract with Election Systems and Software for a new voting system that will be ready beginning next year.

While most other Texas counties do not currently appear ready to pay for new voting machines soon, the problems with straight-ticket voting are not likely to emerge again after Tuesday. Last year, Texas lawmakers agreed to eliminate the straight-ticket voting option beginning in 2020.

Darla Cameron and Ryan Murphy contributed to this report.

Disclosure: Rice University and the University of Texas at Austin has been a financial supporter of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune’s journalism. Find a complete list of them here.

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Matt Zdun was a reporting fellow at The Texas Tribune in 2018. He is a graduate of Northwestern University, where he studied journalism and economics. Before joining the Tribune, Matt worked at CNBC,...