Although it had been a feature of elections in some parts of the United States for years, the phenomenon of mail-ballot voting exploded in the 2020 election. In the midst of the COVID pandemic, jurisdictions around the country expanded use of mail voting, sometimes sending ballots to every registered voter. Steps were taken to facilitate ease of mail voting, such as establishing drop boxes for returned ballots, relaxing rules regarding signature verification, and easing restrictions on “ballot harvesting,” the practice whereby paid political activists collect a large number of completed ballots and return them for counting. As a result, by some estimates, the proportion of ballots cast by mail nearly doubled from 2016 to 2020.

There is, of course, an ongoing debate over whether the turn to mail-ballot voting was necessary, given the pandemic circumstances, or a partisan maneuver to advance the prospects of Democrats, who seemed to reap most of the benefits electorally. Whether or not it was necessary, the development clearly contributed in two important ways to undermining confidence in the results – and is likely to continue doing so unless legislators and election officials take corrective measures.

First, mail-ballot voting is intrinsically less secure than in-person voting. Things might go awry at multiple points. The ballot might never be delivered, or it might be delivered to the wrong address, or to the right address but wrong person. Even if delivered into the right hands, it might ultimately be filled out by someone else or by the intended recipient under pressure; under these conditions, there is no guarantee that the secret ballot is preserved, a problem exacerbated by the activity of ballot harvesters. Once the ballot is completed, it can get lost in the mail, removed from a drop box, or otherwise compromised.

And this is without accounting for the potential for large-scale fraud. In 2020, an unnamed political operative in New Jersey described to the New York Post how he had developed and been using for years a system for replicating ballots and submitting them on behalf of his candidates. Despite the assurances of some that voter fraud is not an issue in the United States, a number of high-profile cases in the last quarter-century prove otherwise. Since 1997, mayoral elections in Miami and Paterson, New Jersey, as well as a congressional election in the Ninth District of North Carolina, have been vacated due to proven fraud. As John Fund and Hans von Spakovsky document in their 2021 book “Our Broken Elections,” these three cases are the tip of the iceberg. Indeed, Fund and von Spakovsky note, most cases of large-scale fraud in recent years have involved mail ballots.

There is a reason France no longer uses mail-in ballots in its elections, and why the 2005 commission led by Republican James Baker and Democrat Jimmy Carter identified mail ballots as the least secure mode of voting (though in 2020 Carter rather weakly tried to walk back that conclusion).

Nearly a year and a half after the 2020 elections, a special counsel has charged that substantial voter fraud took place in more than 90 of Wisconsin’s nursing homes, where it appears that nursing home staff or administrators requested ballots for invalid patients, then filled out and returned those ballots, possibly forging the patients’ signatures. A private study (separate from the controversial Arizona “audit”) alleges that 200,000 mail ballots in Maricopa County were counted despite mismatched signatures.

Overall, one does not need to accept former President Trump’s expansive claims of national voter fraud – indeed, one should not, without a great deal more evidence than he has yet offered – in order to recognize that mail-ballot voting is vulnerable to a number of problems that make it chronically less reliable than in-person voting. Moreover, perhaps as importantly, many voters recognize this fact, and as a result will consistently question the validity of close results in elections using large-scale mail balloting, at least if their candidate loses.

Second, because of significant disparities in the political makeup of the mail-ballot electorate and the Election Day in-person electorate (in states that are not 100% mail ballot), the reporting of election results can become distorted. In the 2020 general election, we witnessed both a much-expected “red mirage” and a lesser-noted “blue mirage.” In a few states such as Texas and Ohio, mail-ballot votes were counted and reported first, leading to initial Democratic leads that were gradually wiped out through the night as Election Day votes were added to the tallies. In most major states, the reverse happened. Election Day votes were counted first, followed by mail-ballot votes. The predicted “red mirage” came to pass as President Trump took early leads in Georgia, Michigan, Pennsylvania, and Wisconsin before surrendering them over the next few days as the mail ballots rolled in.

No one paid much attention to Texas and Ohio, which had their totals in relatively early, and in any case went the way they were expected to go. On the other hand, the “red mirage” states drew enormous scrutiny. They were already understood to be swing states that could go either way and would determine the election. Moreover, all had voted for Trump in 2016. Many Trump supporters went to bed on November 3 with their man seemingly headed to another surprise win, and found out on November 4 that it was slipping away in a process that was not completed for several days. That sensation, of having an election victory subsequently overridden, undoubtedly contributed to the willingness of many to embrace Trump’s “stolen election” narrative. That is an outcome we should hope to avoid in the future.

It is possible that the partisan makeup of mail-ballot versus Election Day voters depends on circumstances. In 2020, Democratic voters may have been more afraid of COVID and hence more likely to avoid voting lines, while Republican voters were urged by their president not to trust mail voting. Perhaps other circumstances will produce different tendencies. Unless both modes of voting are utilized equally by supporters of both candidates, the potential will exist that those who lose based on late-reporting mail results will wonder whether something nefarious happened.

The optimal solution would be to increase in-person early voting opportunities and the number of Election Day polling places, while strictly limiting mail voting to traditional absentee voting for reasons of illness, disability, or absence. However, many jurisdictions continue to be committed to widespread mail voting. It is a practice that is not going away anytime soon, so a key question is what can be done to reduce the damage that mail-ballot voting can do to confidence in electoral legitimacy.

The two problems outlined above – inadequate ballot security and delayed vote totals – require distinct measures.

The chief way to mitigate concerns around delayed vote totals is to enforce a strict Election Day deadline for the return of mail ballots and to require election officials to begin counting received mail ballots prior to Election Day. The other confidence-building measure would be to adopt Georgia’s new requirement that election officials must announce on Election Night the total number of votes received. This will prevent the perception that large batches of incoming votes are materializing out of thin air.

As for ballot security, some states have already taken steps that should be adopted more broadly. These include banning ballot harvesting and improving verification techniques (possibly using the last four digits of Social Security numbers instead of signatures). Not least, state and county election offices should take more seriously their obligation to keep their voter-registration rolls updated. If election officials want voters to be confident in the legitimacy of mail-ballot elections, they need to make sure that no household is getting five extra ballots for residents who haven’t lived there in years. Unfortunately, Democrats have widely condemned such measures as “voter suppression.”

None of these steps would prevent a nominally responsible eligible voter from casting a vote by mail, but they can help bolster confidence in our elections. If we have to learn to live with mail-ballot voting, we should be able – no, eager – to answer legitimate concerns rather than pretend that they don’t exist.