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In 1979, the NBA introduced the three-point line, creating new superstars who could hit the long-range jumper. The bigger long-term impact of the change, though, was to increase the effectiveness of the tallest players, who benefited from stretched defenses.

What is true of sports is also true of elections—even slight adjustments to the rules can tilt the game for or against certain players, and ultimately influence outcomes, sometimes in unanticipated ways.

According to a new study, in 2016, Donald Trump received a 1.7 percent bump in states where he was listed first on every ballot. In some states where he received that benefit, including Florida, Michigan, Pennsylvania, and Wisconsin, he won by less than that amount.

Another recent study showed that increasing the number of days of early in-person voting particularly increased turnout among women and voters in their 20s. According to the authors, if every state in 2016 had provided 23 days of early voting, Hillary Clinton would have won Florida, Michigan, Pennsylvania, and Wisconsin―and the presidency.

The uncertainties caused by COVID-19 have led a number of states to examine and adjust the rules for the November elections. Thus far, most of the planning has focused on how states will handle the predicted demand for voting by mail. There is no question that voting by mail is an important part of the solution. It mitigates the problems of long lines and fosters social distancing. But the specific rules used to implement vote by mail may determine whose vote is counted and whose is not.

Experience and past election results show that in order to prevent vote by mail from inadvertently disenfranchising voters, states must adopt four key safeguards:

(1) Postage must be free or prepaid by the government.

(2) Ballots postmarked on or before Election Day must count.

(3) Signature-matching laws need to be reformed to protect voters

(4) Community organizations must be permitted to help collect and deliver voted, sealed ballots.

We know that lack of pre-paid postage is an impediment to voting for many lower-income and young voters, and experts have found that requiring voters to have mail ballots received by Election Day, rather than simply post-marked by Election Day, has a disproportionate impact on minority voters. In 2016, a determination that a voter’s vote-by-mail signature failed to match the signature on file was the most common reason for rejecting a ballot. Finally, experience shows that laws that prevent community organizations from assisting voters with the collection and delivery of voted and sealed mail ballots disadvantage minority voters.

Safeguarding vote by mail is only a part of the solution. Some voters—and in particular many minority voters—strongly prefer voting in person, either because of historical mistrust in the vote-by-mail system or because of the expressive nature of showing up at the polls. Accordingly, states must provide voters who prefer voting in-person a safe and available option for doing so.

Here, too, there are specific steps states should take to avoid excluding voters.

First, states must guarantee adequate staffing at polls by turning to staff at state agencies and to students. Even in the best of times, recruiting, training, and deploying enough poll workers for in-person voting is a challenge. In 2018, 68 percent of poll workers were over 60 years old and more than a quarter were over 70. Government employees should receive overtime pay for working Election Day, and college and high school students should receive both pay and course credit for their effort.

Second, states should expand curbside voting for voters of all ages. This would allow voters to drive up, receive a ballot, and return it to be counted—all without leaving their car. Many states provide this service for disabled or elderly voters. It should be expanded for everyone.

Third, states must expand early voting to include weekend voting. This would minimize long lines and facilitate voting for those who can’t get to the polls on Election Day.

Fourth, all states should adopt vote-anywhere rules. Voters who show up at the wrong polling location should be allowed to vote a ballot for those offices for which they are eligible. Some states currently allow this, but others force these voters to cast a provisional ballot that, more often than not, doesn’t count.

Finally, states should develop systems that allow voters to sign up to reserve a time to vote during off-peak hours. Such a system would reduce lines by incentivizing voters to show up during non-peak times.

The goal should be to avoid letting the rules dictate who wins based on whose voters can participate. Only by taking these steps can we be assured that the rules of the election won’t unfairly tilt the playing field.

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