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Even in ordinary times, voting is hard for many Americans, requiring them to wait in long lines and, in some cases, forgo wages as a result. Of course, these are not ordinary times. Today, and possibly even this November, the potential cost of casting a ballot in person on Election Day could be considerably higher, given that crowds and shared surfaces (such as the interface of an electronic voting machine) present perfect environments for spreading the coronavirus.

The election is too important to let fall prey to this virus. Americans must ensure that the country’s democratic process moves forward as scheduled. And there is one time-tested and straightforward way to do that: nationwide vote by mail.

The question of expanding access to voting by mail should not be left to the states to decide. The country needs a federal law that ensures all citizens may exercise their right to vote, without having to jeopardize their health. Congress should swiftly pass a law that mandates the option of early voting by mail in all 50 states and the District of Columbia.

A ready-to-hand legislative vehicle already exists for achieving this. In pending relief legislation, the Senate has proposed providing states with more than $400 million in assistance to help support the 2020 general election, which could cover expenses for rolling out and running voting by mail, in addition to monies for more polling places, poll workers, and voting machines. But this is not enough. Financial incentives, although important, are not the same as a direct mandate to make voting by mail available to all citizens who wish to use it. Congress need not ban in-person voting absolutely, but should merely require that a mail-in ballot automatically be sent to each and every registered voter (regardless of whether a voter affirmatively requests one). It would then be up to individual voters either to use that mail-in ballot or to vote in person on Election Day.

Absent a clear and unequivocal federal mandate, some jurisdictions—those that most want to suppress the vote—will still require in-person voting and simply not take the subsidy for mail-in voting systems. The arguments against providing voting by mail are easy to anticipate: We must check photo identification to avoid voter fraud. Mail-in ballots are not secure—people will steal them and mail them in, stuffing the ballot box. We do not have the time or capability to alter our election procedures in time for November 3.

These arguments are specious, and Congress should reject them. If serious, systematic problems with voting by mail existed, they would have already presented in Washington, Oregon, and California, where the option is available to a combined 50 million residents. (Oregon has used mail-in voting for more than 20 years.) No widespread issues, such as ballot theft or fraud, have arisen in these jurisdictions with respect to mailing in physical ballots. Indeed, Washington has experienced several very close elections, including the 2004 gubernatorial race, in which the Democrat, Christine Gregoire, defeated the Republican, Dino Rossi, by a margin of 129 votes (out of 2.8 million cast). Rossi’s campaign, which certainly had good cause to be disappointed with this outcome, never suggested that voting by mail compromised the fairness or integrity of the election. In this sense, these states have served as “laboratories of democracy,” to use Justice Louis Brandeis’s wonderful turn of phrase. Accordingly, Americans do not have to guess about whether mail-in voting works; it clearly does. (Corporations and credit unions also routinely use mail-in voting for board elections without problem.)

The same cannot be said (at least not yet) for smartphone–based voting. Earlier this year, Seattle used app-based voting for elections to seats on the King County Conservation District (an obscure administrative agency that has suffered very low levels of voter participation for its elections). Computer-security experts expressed grave misgivings about the safety and security of this voting process, and serious problems also arose with an app used to report vote totals in the Iowa and Nevada caucuses. One day app-based voting might be a viable option for conducting a national election, but that day has not yet arrived.

To be sure, both legally and historically, the states take primary responsibility for running elections (including for seats in the U.S. House and Senate). That said, the Framers gave Congress the final say-so regarding congressional elections. The Constitution provides that “the Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof.” The same clause also adds a crucial caveat: “But the Congress may at any time by Law make or alter such Regulations.” Thus, Congress has the power to impose uniform national rules, including for voting procedures (at least with respect to elections for House and Senate seats.)

Congress has in the past used this power to make it easier to register and vote. In 1993, for example, Congress enacted and President Bill Clinton signed the National Voter Registration Act, commonly known as the “Motor Voter Act,” which requires states to offer voter registration to citizens when they appear at the DMV to obtain a driver’s license.

A recalcitrant state could override the federal mandate and require in-person voting for local and state elections and for presidential electors, because Congress does not enjoy explicit constitutional authority to set the rules for these contests. (Voters technically do not vote directly for presidential candidates, but rather for a slate of presidential-elector nominees pledged to support a particular candidate, and the Constitution gives state legislatures carte-blanche control over the selection of electors.) Precedent at least suggests that no state will do this: Under the Motor Voter Act, for example, states have not adopted dual-registration systems; the “motor voter” registration is good for all elections within the jurisdiction. What is more, governors of both political parties have already rescheduled presidential primaries to mitigate the virus’s spread. Mike DeWine, the Republican governor of Ohio, took extraordinary steps to postpone the state’s primary, as did John Bel Edwards, the Democractic governor of Louisiana. It seems highly unlikely that a governor who would stop an election by fiat to promote public health would object to providing mail-in general-election balloting for the very same reason.

As a more basic matter, a national system of voting by mail would make it easier for ordinary Americans to vote. They would no longer have to queue in lines for hours in overcrowded urban precincts in places such as Cleveland, Detroit, and Miami. They could vote from the comfort—and safety—of their own homes.

With more than six months until the election, creating and implementing such a system should not be difficult. If necessary, the Department of Commerce could make its census database available to state election offices that might face gaps in voter information.

The outcome of allowing vote-by-mail is difficult to predict. Many of the voters most likely to stay home this November—older voters in retirement communities such as The Villages near Orlando, Florida, who are at high risk of getting COVID-19—tend to support the GOP. Because the health risk could easily suppress GOP voter turnout, Republican members of Congress should see a political reason—to say nothing of a moral one—to embrace a vote-by-mail mandate. As for the cost, ensuring that America’s national election takes place on a timely basis and permits as many citizens as possible to vote is, quite literally, an investment in democracy itself. What could be more essential to a nation whose founding document credits “We the People” with the very existence of the federal government?

America’s governing institutions derive their legitimacy from this imprimatur. To preserve that legitimacy in an era of an airborne pathogen that causes serious illness and death, on a seemingly random basis, citizens should not be required to physically go to a polling place in order to exercise their franchise. Luckily, they don’t need to, if only Congress would act.

This story is part of the project “The Battle for the Constitution,” in partnership with the National Constitution Center.

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