“Print the word vote upside down, but in the correct order.”

If you have no idea what that means, you’re not alone. That’s Question 21 on a “literacy test” given to some black voters in Louisiana in 1964 to try to prevent them from voting. There were 30 questions on the test, all worded confusingly by design. If you got one question wrong, you were turned away from the polls. Absurdly, voters had just 10 minutes to complete the test, leaving 20 seconds per answer. When that test was given to a group of Harvard undergraduates recently, none passed. Had they been black voters 56 years ago in Louisiana, they would have been disenfranchised.

Thankfully, Jim Crow trickery like this is a thing of the past. But more subtle forms of voter suppression have replaced the tests.

Minority voters still have a much harder time voting than white voters. Some disparities are related to onerous voter identification requirements, which disenfranchise minority voters more than white voters. (Roughly 91 percent of white Americans have a valid form of photo identification, compared with 83 percent of Hispanic Americans and 73 percent of African Americans.) But perhaps the most sinister form of minority voter suppression is also the simplest: making nonwhite people wait longer to vote.

In the 2016 election, researchers aggregated smartphone user data to see how long voters were spending waiting in line to cast their ballot. What they found was a disgrace: Those who tried to vote in black neighborhoods waited significantly longer than those who tried to vote in white neighborhoods. And voters in heavily black neighborhoods were 74 percent more likely to have to wait at least 30 minutes in order to vote.

It’s not just an injustice; it’s also an insidious threat to democracy. The longer people must wait to vote, the fewer people will have their voices heard. Some will wait and eventually leave. Others will give up on voting entirely after spending hours in line.

While wealthier voters can easily cope with an hour spent waiting in line, precariously employed poorer voters — who are often members of minority communities — are less able to take time away from work to vote. It’s the worst of both worlds: The voters who can least afford to wait are those who are most likely to have to.

We’ve replaced Jim Crow-era poll taxes with modern-era time taxes.

In many cases, long lines are part of a deliberate strategy to disenfranchise minority voters. Since a 2013 Supreme Court ruling weakened minority voter protections in states with a history of racial discrimination in voting, more than 1,000 polling locations have been shuttered, many in majority-black neighborhoods. Texas, Arizona and Georgia were the worst offenders, though there were significant closures in Louisiana, Alabama and Mississippi as well. Again, those hit hardest are most likely to be poor voters in minority communities, not just because they face longer wait times but also because getting to a further afield polling location is harder for those who don’t own a car.

This is being done primarily by Republicans for partisan gain. Black voters are overwhelmingly likely to support Democrats. In 2016, an estimated 89 percent of black voters cast ballots for Hillary Clinton. In fact, given the dismal polling for Republican candidates nationwide, it’s likely that the Republican Party will make more electoral gains by suppressing minority votes than by trying to win them over in the coming months. And the GOP knows it.

So far there is no federal law to prohibit waiting burdens that fall disproportionately on minority voters. That needs to change. In 2014, a federal review recommended that voters should not wait more than 30 minutes from arriving at a precinct to casting their ballot. It’s time to shift that from a recommendation to a legal mandate.

Even though states oversee their own voting rules, there is a way that a new federal law could address the problem. States would need to ensure that voting wait times are, on average, less than 30 minutes in all counties and ensure that there is no significant disparity between wait times in minority-dominated precincts and white-dominated precincts. Failure to comply would lead to a loss in federal funding.

For noncompliant states, the law would also prescribe a simultaneous boost in funding slated only for election administration in precincts with long wait times. That would help to ensure that any funding cuts don’t exacerbate the problem further. There could also be a pot of additional federal funding that states compete to win based on reduced wait times and low racial disparities.

We would never stand for such glaring racial disparities in wait times in the private sector. Imagine calling a customer support line for Verizon or AT&T and being asked to dial 1 if you’re black or 2 if you’re white and having your wait time correspond to that selection. And yet we accept it as a normal functioning of the most fundamental process in our democracy. A legal mandate for wait times won’t solve every problem with minority voter suppression, but it would be an easy — and important — step in the right direction.

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