Indiana's voter-ID law is harmful and worthless.

This Wednesday, in the midst of an intense political primary season, the Supreme Court will hear a case that will say a lot about the kind of democracy America aspires to be. At issue is an Indiana law requiring registered voters to present a government-issued photo ID when they seek to vote on Election Day. A law said to combat voting fraud by imposing the modest task of showing an ID may seem at first impression to be both sensible and fair. But this law is neither.

First and foremost, Indiana's law is a "solution" to a problem that doesn't exist. The voting fraud it purports to address is illusory. And the means it employs needlessly make it far more difficult for some citizens—especially those who are low-income, elderly, or lack easy access to transportation—to vote.

The basic legal standard for assessing a voting restriction of this sort is whether the need for the restriction is sufficiently weighty to justify the burden on legitimate voters. Photo-ID supporters argue that the requirement is necessary to prevent voter fraud, and that it imposes a negligible burden because legitimate voters invariably possess a government-issued photo ID. Both claims are wrong: A photo-ID requirement, in fact, is essentially of no benefit in preventing voter fraud, and it disenfranchises scores of legitimate voters.

There is no dispute that Indiana's photo-ID requirement addresses one, and only one, species of fraud—so-called "in-person impersonation fraud," which would occur if an ineligible voter were to come to the polls and attempt to cast a ballot by falsely claiming the identity of an eligible voter. In the entire history of Indiana, the total number of reported instances of this kind of fraud is zero. Nor is there reliable evidence that in-person impersonation fraud has occurred anywhere else in the country.

That is not surprising, as this kind of fraud would be an exceedingly irrational way to attempt to affect the outcome of an election. For starters, the impersonator would need to know that the actual registered voter would not herself be showing up to vote. If the real voter had already voted, the impersonator would be exposed at once. And in any event, why would any sane person risk going to prison to influence an election by one vote? It is all the more implausible to imagine an army of impersonators coordinating their efforts on a scale that could affect an election, let alone doing so without being detected. That is why the election fraud that's actually been tried involves ballot-box stuffing or bulk submitting of absentee ballots—schemes that allow a few people to roll up a lot of fraudulent votes. A photo-ID requirement does nothing to prevent those real shenanigans.