A small number of Harris County voters received incorrect ballots on Election Day, an error the county clerk says was the fault of poll workers amid a shift to allowing residents to visit any polling station.

Michael Winn, Harris County’s director of elections, said the clerk’s office knows of three locations where the problem occurred: Wilson Montessori, Lazybrook Baptist Church and Freed-Montrose Library. In some cases, Winn said poll workers were too slow to check in a voter. If the voting system times out twice, the poll worker has the discretion to choose which ballot a voter receives, which led to errors.

“They have two times to mess it up before it can go wrong,” Winn said around midday. “It's a training issue. We've contacted all our locations to make sure it doesn't happen again.”

This is the highest-turnout election to date in which Harris County has used its new countywide voting system, where residents can visit any polling station on Election Day, instead of an assigned precinct. In this system, electronic poll books can generate the correct ballot for any voter.

County Clerk Diane Trautman, a Democrat elected last year, has said the shift will make voting more convenient and increase turnout.

Allison Tanton, who visited the polling station at Lazybrook Bapist Church, said she noticed the District H City Council race on her ballot instead of the one for District C. Tanton said she asked a poll worker about the discrepancy. After speaking on the phone with county elections officials, who verified her address, Tanton said she was given the correct ballot and cast her vote.

Tanton said about four other voters at the site also received incorrect ballots during her 20 minutes there.

“It seemed concerning it was happening multiple times while I was there for a short period of time,” Tanton said.

Sean Carroll said he and several other voters had a similar experience at Wilson Montessori. Carroll said he was about to cast his vote when he realized his ballot was wrong. A poll worker verified the mistake and Carroll said he was able to cast a new ballot.

Montrose resident George Ference said he and his wife were given the wrong ballots when they arrived at the Freed-Montrose Library polling site Tuesday morning. He said poll workers were not immediately able to fix the problem.

“We were unsure how to proceed, and we had received no instruction after 10, 15 minutes of waiting around,” he said. “I was going to be late for work, so I cast the ballot that I had already started.”

Winn, the elections administrator, said the county’s voter databases are accurate. He said voters should review ballots to ensure they are correct and contact poll workers if they spot any errors.

“If the voter hits ‘cast ballot’ on the wrong one, there's nothing anyone can do to fix it,” Winn said.

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