Hi, folks.

Ahead of the Wisconsin Supreme Court election in April, Green Bay election officials accidentally sent 150 voters duplicate ballots, leading to an administrative complaint before the Wisconsin Elections Commission and conspiracy theories online.

In a slightly different example also from this year, some voters in Maryland initially received ballots for the wrong party. Election officials then intentionally issued ballots for the correct party, and the original ballots were voided. Nonetheless, President Donald Trump falsely suggested that nobody knew what was happening with the original ballots.

Despite the heightened attention on the mistakes, election officials accidentally sending out duplicate ballots — or sending out an erroneous batch and then intentionally sending the same voters correct ballots — is a rare but well-understood mistake nationwide that hardly ever results in problems. 

“Once any ballot is received and accepted, it locks down that voter's record, so that a second ballot could not be accepted for that same voter,” said Tammy Patrick, chief programs officer of the National Association of Election Officials. “That's the way it works everywhere.”

Two primary mechanisms keep these accidental double ballots from getting counted: proper record-keeping and deterrence, said David Levine, an election security expert who’s the election director in Richmond, Virginia. Generally, that record-keeping is done by putting unique barcodes on absentee ballot envelopes, which prevent people from voting more than once.

“It's usually not an issue because, one, election officials are pretty good about contingency planning and having procedures in place, so if something like this happens, they know how to either write void ballots or segregate them appropriately, so that they're not going to be counted,” Levine said. 

Secondly, he added, most voters understand that double-voting is a crime, and it’s a practice they just don’t want to engage in. A study of 2012 election results found that one in 4,000 votes cast was a double vote. And that’s a generous estimate: The researchers also concluded that clerical errors in marking turnout records may account for most if not all of those purported double votes.

One of the best tools election officials have at their disposal in Wisconsin and other states are unique barcodes printed on the absentee ballot certificates that voters receive. 

In Wisconsin, those barcodes connect to the statewide voter registration database and are unique to each voter. Other states have similar systems, with unique identifiers tying an absentee ballot to each voter. If an election official scans a duplicate ballot, they’ll see that a voter already returned one, and one of the ballots will be rejected.

That’s a “very, very established process,” Wisconsin Elections Commission administrator Meagan Wolfe said after the Green Bay incident.

I’ve got more on this coming soon. Stay tuned for that.

Let me know what questions you have about elections in Wisconsin. You can reach me at [email protected] or by replying to this email. 

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