Barry Burden, Rob Stein, and Charles Stewart:

As the novel coronavirus pandemic besieges the United States, more and more observers are suggesting that November’s votes should be cast by mail — allowing the least possible in-person contact, reducing health risks to both voters and poll workers.

But shifting millions of voters to mail balloting would bring other risks. First, voting by mail includes many steps between someone’s request for an absentee ballot and delivering that ballot to be counted — gaps that ballots can fall through. Second, voters can make mistakes marking the ballot that they may not be able to correct.

If states do significantly expand their voting by mail, will they be able to reduce these risks?