President Trump is suing Nevada over its recent decision to send absentee ballots to all voters, and warning the country “There is NO WAY (ZERO!) that Mail-In Ballots will be anything less than substantially fraudulent.” Trump’s critics argue that there is no evidence that voting by mail results in fraud. Trump is right that mail-in voting is a source of potential voter fraud, especially on the scale that is being proposed. But the bigger problem is not vote fraud — it’s vote failure.

There is plenty of evidence that mail-in voting has the unintended consequence of disenfranchising of millions of eligible voters. A Massachusetts Institute of Technology study of the 2008 presidential election found that about 3.9 million voters said they requested mail ballots but never received them; 2.9 million ballots that were sent out did not make it back to election officials; and about 800,000 were rejected for a variety of reasons — either because they were postmarked after the election, arrived without a signature, were improperly filled out or did not match voting records. “The pipeline that moves mail ballots between voters and election officials is very leaky,” the study concluded.

More recently, the 2020 Democratic primaries should serve as a cautionary tale. About six weeks after New York’s congressional primaries, winners were not declared in two closely watched House races until Tuesday. That’s thanks to complications in counting the surge of more than 400,000 mail-in ballots, of which state officials have already invalidated 84,000. In California, election officials rejected more than 100,000 mail-in ballots in the state’s March presidential primary. To put these numbers in perspective, Trump won the White House in 2016 thanks to roughly 80,000 votes in Michigan, Pennsylvania and Wisconsin combined. In Pennsylvania alone, mail ballot problems kept about 92,000 people from voting in a primary in a state that Trump won by just 44,000 votes four years ago. In Florida, about 18,500 mail-in ballots were not counted, and in Nevada, about 6,700 were rejected. In a close race, such failures could easily call the results into question.

None of these problems were because of fraud. They were because of mistakes by voters, postal problems or the inability to handle the massive surge in ballots that overwhelmed electoral systems not equipped to handle them. If election officials had this much trouble handing mail-in ballots during low-turnout primaries, imagine what will happen in the general election. Put aside the ability of election officials to process the results. Does anyone believe that the U.S. Postal Service is ready to handle a sudden deluge of tens of millions of ballots right before Election Day? Millions of ballots are inevitably going to be delayed, be misdirected or arrive without postmarks. And many will be invalidated because voters made mistakes filling them out and could not ask election workers for help marking the ballots correctly.

If mail-in voting is permitted on an unprecedented scale, millions of votes will be rejected and the election could be thrown the election into chaos. Ironically, it could very well be Democrats who end up crying foul. A study of Georgia’s 2018 midterm elections found that mail-in ballots of “younger, minority and first-time voters are most likely to be thrown out.” A study of Florida’s midterms that same year determined that mail-in ballots “cast by Black, Hispanic, and other racial and ethnic minorities were more than twice as likely to be rejected as … ballots cast by White absentee mail voters.” Democrats now pushing for mail-in ballots will soon be claiming they are a tool of voter suppression.

The Democrats’ solution to these problems is to relax the standards for mail-in ballots, such as the requirement that they be postmarked. Now that is an invitation to fraud. If a candidate is narrowly behind on election night, what is to stop their supporters from sending in a slew of ballots after Election Day — especially in states that permit “ballot harvesting,” where campaign workers collect absentee ballots in bulk? There will be millions of blank ballots in circulation, because instead of sending ballots only to voters who request them, many states intend them to send to every registered voter — which inevitably includes many who moved or died.

This probably does not matter in deep-blue and deep-red states where the final result is not in doubt. But in swing states such as Nevada, Wisconsin, Michigan and Ohio, it could lead to disaster — even if there is no fraud. Most states have no experience with mail-in voting on this scale and are completely unprepared for what is coming. We are conducting an unprecedented electoral experiment in the midst of one of the most contentious elections in U.S. history. The result could be a post-election battle that will make the hanging chad controversy of Bush v. Gore seem mild by comparison.

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