LAFAYETTE (KPIX 5) — While there has been an increasingly sharp focus on vote-by-mail ballots in the November election, some voters in Contra Costa County are still sorting through voter rolls tainted by a case of voter registration fraud four years ago.

“So, this whole street, there’s only three houses,” explained Lafayette resident Jack Shawn as he he gestured at other homes in his neighborhood. “I know everybody that has ever lived here and none of them are those people.”

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Shaw has received his 2020 vote-by-mail ballots: a couple that he was expecting, and two more with names he has never seen before.

“This is my ballot that I opened up,” said Shaw with his ballot in hand. “This is my daughter’s. And these two people I don’t know.”

KPIX took his questions to the Contra County County elections office. As soon as they heard about unexpected ballots, they had an idea of what was going on.

“I knew the rest of the story,” said  Contra Costa County Assistant Registrar of Voters Scott Konopasek. “I have heard it many, many times.”

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Konopasek said the mystery ballots are probably the lingering aftermath of a voter registration fraud case from the last presidential election.

“In October of 2016, just prior to the previous presidential election, we started getting calls from voters in Lafayette saying, ‘I’ve received all these ballots,'” Konopasek explained. “We started to see a pattern: that these registrations were all done by one particular signature gatherer who was also registering voters.”

Elections officials caught it, handed the case over to the district attorney and tried to strike all of the bogus names from the voter rolls. Still, some surfaced in 2018 and now again in 2020, so the work continues.

“In the meantime, voters continue to call us because they notice that they’re getting mail like this. We’ve cleaned up hundreds of records so far but apparently there are still more out there,” Konopasek said. “The only way we will know is if voters tell us if there’s a problem.”

Anyone who thinks they have received a ballot sent to someone that does not exist should contact their county elections office.

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The man charged in the 2016 case ultimately pleaded no contest to a misdemeanor after initially being charged with a felony.