Wisconsin, North Carolina, and South Carolina are among the most closely watched states in the 2020 election, for good reason. The first two, as swing states, could affect who wins the White House, while the latter two have close Senate races that could determine which party controls Congress. They also have something else in common: the dubious distinction of being among the handful of states that require a witness signature on absentee ballots.

As a security matter, demanding a second signature on a mail-in ballot is “utterly useless,” notes Phil Keisling, former Oregon Secretary of State, and a Washington Monthly contributing editor. Vote-by-mail systems in nearly all states already check voter’s signatures against voter registration records, so requiring a witness signature amounts to a “superfluous and unnecessary obstacle to voters,” he adds.

The requirement is particularly burdensome for older voters who live alone and have difficulty finding witnesses, especially in the middle of a surging pandemic. Understandably fearful of leaving their homes to find a co-signer, these voters are forced either to mail in their ballots without a second signature and risk having them thrown out or not vote at all if they can’t find someone to sign for them. That’s why state courts over the last several months have overturned witness signature mandates in Rhode Island, Virginia, Minnesota, and Alaska. Yet such restrictions are still on the books in Wisconsin, North Carolina, and South Carolina. Sure enough, that has already created problems. In North Carolina, for instance, the Associated Press reported last month that  “lack of a witness signature or other witness information has emerged as the leading cause of ballots being set aside before being counted in North Carolina, with problems disproportionately affecting Black voters in the state.”

In past elections, the requirement has not been much of a problem because few people in these states voted absentee and, if they did, they had a handy workaround. They could get their local letter carriers to co-sign their ballots or ask a clerk at their local post office to do so.

In this election cycle, however, not only are vastly more residents choosing to vote by mail—absentee ballot requests in Wisconsin, for instance, have more than doubled compared to 2016—but, in a much under-covered move, the U.S. Postal Service under Postmaster General Louis DeJoy issued an order this summer forbidding Postal Service employees from providing witness signatures on voters’ absentee ballots.

Over the last several weeks, postal union officials have pushed DeJoy’s top lieutenants to rescind the prohibition. They’ve argued that it’s a service that letter carriers and clerks have long offered and is more necessary than ever in an election marked by COVID-19 and record levels of absentee voting. Last week, however, the USPS national management refused a final plea from the unions to reverse the order.

That could have major implications. Presidential polling margins in North Carolina and Wisconsin are narrow: +1.8 for Biden in the former, +4.6 for Biden in the latter, according to the latest Real Clear Politics average. And the Senate races in South Carolina between Lindsey Graham and Jaime Harrison and in North Carolina between Thom Tillis and Cal Cunningham are similarly close. If enough voters are impacted by the witness signature requirement in those states, it could influence the outcome of the election.

In mid-July, USPS issued the order forbidding postal employees from co-signing mail-in ballots, according to Vice. This was around the same time that DeJoy was enacting policies that dramatically slowed mail delivery. “As the 2020 election cycle continues, customers may ask retail clerks to sign mail-ballot envelopes as witnesses,” warns an August 18 memo sent by USPS headquarters to postal employees. “The Postal Service should not provide a witness signature in their official capacity.” (Emphasis theirs.)

After a backlash from lawmakers and activists—and lawsuits from multiple state attorneys general—DeJoy paused most of the USPS’s cost-cutting measures, including getting rid of sorting machines in processing centers and blue mail boxes nationwide, until after the election. But the order barring USPS employees from providing witness signatures got nowhere near as much attention from DeJoy’s critics—possibly because its effects would only be felt in a handful of states. It remains in force.

The only organizations that have tried to get USPS to drop the rule have been the four major postal unions—the American Postal Workers Union, the National Association of Letter Carriers, the National Rural Letter Carriers Association, and the National Postal Mail Handlers Union. They have been conducting weekly meetings since early this summer with the Postal Service’s national leadership to ensure a smooth vote-by-mail election. During an October 15 meeting, union representatives pushed DeJoy’s senior advisers to reverse the witness signature order, especially since voting is well underway across the country.

One week later, on October 22, the officials said they would not undo the order, citing the need for operational efficiency—the same rationale DeJoy used to defend some of the USPS’s other moves—and that it was too late in the process to initiate a policy change. Those arguments infuriated APWU President Mark Dimondstein. “It’s an insult to postal workers—to think we can’t do this,” he told me. “It’s the most trusted agency. I mean, we process passports, for crying out loud. Why wouldn’t we be able to help people cast their ballot?”

The Postal Service also claims that the ban on co-signing ballots is a longstanding policy. “Postal Employees are prohibited from serving as witnesses in their official capacity while on duty, due in part to the potential operational impacts,” David Partenheimer, a USPS spokesman, told me. “This policy has not changed.” When I asked him to provide evidence that the policy existed before the election, I got no response. Officials from the National Association of Letter Carriers have gone scouring through old records in recent weeks and could find no trace of the policy before this summer.

The assertion that the ban on USPS employees co-signing absentee ballots is a longstanding one was certainly news to voters in Alaska, where residents in remote parts of the state have relied on the service for decades. In August, elections officials were stunned when they received an influx of complaints from customers saying their letter carriers told them they could no longer sign their ballots. “Sooo [sic] I went to the post office to mail my absentee ballot, and even tho [sic] it says very clearly on the instructions that postal officials can sign your witness affidavit, the folks working the counter downtown said they were not allowed,” wrote one voter on Twitter. “Why?”

The state’s elections director then reached out to the Postal Service for clarification. Within 24 hours, USPS confirmed the order. “There has never, never, in my 40 years of dealing with this, ever been an issue,” Jim Raymond, the branch manager of the National Association of Letter Carrier’s district that covers the Anchorage area, told me.

Luckily for Alaskans, the state’s Supreme Court ruled this month that voters wouldn’t need a witness signature to cast absentee ballots in that state. Voters in Wisconsin, North Carolina, and South Carolina will not be so fortunate. Elections officials in all three of those states told me that until July, they had never heard of a rule banning postal employees from co-signing ballots.

How the ban might affect election outcomes will be hard to know, even after November 3. Neither the USPS nor elections boards have ever bothered to keep track of how many ballots are co-signed by postal workers. Moreover, the real measure of the ban’s impact would involve calculating how many voters in those key states, many of them voting by mail for the first time, might have asked a postal worker for help had that option been available and publicized by USPS, campaigns, elections boards, and the media. Instead, of course, the opposite is the case. What’s clear is that if USPS leadership wanted to limit the number of mail-in ballots without incurring provable blame, this would be a good way to do it.

Eric Cortellessa

Eric Cortellessa, a Washington Monthly contributing editor, is a staff writer for Time magazine.