"The algorithm and the election officials almost always get it right. In this instance, it was simply a button that was left checked in the menu option for the algorithm," says Sean Dugar, the consulting executive director of the California Ranked Choice Voting Coalition. It is one of two groups that caught the error.
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As he explains, in the ranked choice voting program, votes can be handled in two ways. In the first way, if a voter skips their first choice, that vote is suspended, or skipped. But in Alameda County, the correct setting should have advanced the second choice to become the first choice. That matters in ranked choice voting where candidates are eliminated in every round.
"If you do it in the correct order, where no candidate is eliminated, and then you count these ballots, then it made the difference," say Dugar.
That difference means that Mike Hutchinson, who finished third, is now the likely winner over Nick Resnick.
VIDEO: Confused about ranked-choice voting? Here's how it works
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In a statement to ABC7 News, Tim Dupuis, the Alameda County Registrar of Voters explains, "There are jurisdictions outside of California that require (Ranked Choice Voting) to be handled the first way. That is why the configuration exists in the system.
Dugar says the error was caught after their partner organization ran the cast vote record, which is essentially a recount - a common practice Dugar says, which is often done after every election since it is public record.
"It is up to us to make sure that we have the checks and balances in place to ensure that vote count is accurate. And in this instance we had the checks and balances. The cast record was released," says Dugar. "Again, it didn't make a difference in any race, with the exception of Oakland School Board District 4 race."
The Oakland Branch of NAACP missed the mid-November deadline to demand an initial recount. But given the error in the school board race, they are demanding a manual recount in all of the Oakland's elections, even though Oakland has been using ranked choice voting for over a decade.
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"We think that the integrity, if there is any integrity in this election, that a manual recount will might bring about some credibility," says Allie Whitehurst, the political action chair of the Oakland branch of the NAACP.
The California Ranked Choice Voting Coalition is also calling for the Alameda County Registrar of Voters to conduct a manual recount of the Oakland mayoral race, at their own expense, "to restore trust in our local elections."
Dugar says it is up to the county if they decide to do so.
Another issue for the county is how to re-certify the election in an election outcome that is unprecedented.
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