In 2013, in Shelby County v. Holder, the Supreme Court declared unconstitutional one of the most effective protections against racial discrimination in the 1965 Voting Rights Act. The decision effectively relieved states with a history of disenfranchising Black voters from the requirement to submit changes in election laws or procedures for preclearance by the federal government.

Thirteen years later, the damage is clear. States freed from federal oversight, many of them states of the old Confederacy, have adopted new restrictions on voting that dramatically dilute non-white voting power. Subsequent court decisions have weakened protections against racial discrimination at the ballot box even further.

Writing for the 5-4 majority in Shelby, Chief Justice John Roberts conceded that preclearance had sharply reduced racial discrimination in “the covered jurisdictions.”But Roberts asserted that “things have changed” now that “the tests and devices that blocked access to the ballot have been forbidden nationwide for over 40 years.”Since voter registration and turnout among Black Americans had surged, Roberts concluded that a coverage formula based on decades-old conditions could no longer justify treating some states differently from others.

But as Justice Ruth Bader Ginsburg pointed out in her dissent, eliminating preclearance because it succeeded was like “throwing away your umbrella in a rainstorm because you are not getting wet.”Old barriers may have fallen, she added, but “the evolution of voting discrimination into more subtle second-generation barriers is powerful evidence that … preclearance remains vital to protect voting rights and prevent backsliding.”In “An American Problem: How the Country Built — and the Supreme Court Broke — the Voting Rights Act,” Michael G. Miller and Kevin T. Morris provide an avalanche of evidence that Ginsburg was right.

“Free to do whatever they wish,” counties across all or part of the 15 affected states, the authors indicate, adopted policies that reduced the turnout of qualified minority voters by hundreds of thousands — perhaps millions.

Had preclearance remained in place, the authors estimate, “Americans of color would have made up a majority of voters in 15 more lower-house legislative districts in 2022.”Minutes after NPR announced the Shelby County decision, Greg Abbott, then the attorney general of Texas, tweeted that the state’s strict Voter ID law, which had been blocked under preclearance, “should go into effect immediately.”Less than 24 hours later, Texas required voters to present photo identification at the polling place.

In 2021, Texas redrew its legislative districts in ways that “never would have taken place” if preclearance were still required, and imposed new voting restrictions disproportionately harmful to minority voters. More than 10 percent of the individuals who began the mail-in ballot process in 2022 were rejected, an order of magnitude higher than the national average. In 2023, after Democratic officials tripled the number of polling places in predominantly Democratic Harris County, the Republican-controlled state legislature restricted the autonomy of Harris County — and only Harris County — to administer its own elections.

In North Carolina, legislators sought data on voting patterns by race before adopting restrictions on early voting and identification requirements that, a federal appeals court subsequently concluded, targeted Black voters “with almost surgical precision.”Other states have found their own methods to make voting more difficult for minority voters. Georgia shortened the time voters have to request absentee ballots and restricted access to ballot drop boxes. South Carolina prohibited ballot drop boxes and tightened absentee voting requirements. Montana ended Election Day voter registration.

A district court judge found that Florida intentionally discriminated against Black voters through its restrictions on registration and the use of drop boxes. He ordered Florida to submit future changes for preclearance for 10 years, but the order was overturned by the 11th Circuit Court of Appeals.

Before Shelby, covered jurisdictions had to demonstrate that proposed changes to voting rules would not discriminate against minority voters. After Shelby, the burden shifted to voters and civil rights organizations to challenge discriminatory rules in court, an expensive, time-consuming and uncertain process.

States can now adopt restrictive voting rules, hold elections under them, and defend the process through years of litigation. Even if challengers ultimately prevail, they can’t rerun past results. Nor did the Supreme Court’s assault on voting rights end with Shelby.

In 2021, in Brnovich v. Democratic National Committee, the court made it harder to challenge voting restrictions under Section 2 of the Voting Rights Act. This year, in Louisiana v. Callais, it sharply limited the ability of minority voters to challenge electoral districts that dilute their voting strength.

The cumulative effect has been to stymie both pillars of the Voting Rights Act: preventing discriminatory new rules before they are implemented and challenging them afterward.

If the Democrats gain control of Congress, they are likely to try to restore preclearance by adopting a new coverage formula based on recent evidence of discrimination. But President Trump is certain to veto such legislation. So unless the Supreme Court admits it was wrong to conclude America has changed enough to dispense with preclearance and other safeguards, what Miller and Morris call “nefarious policy innovation” is likely to continue or accelerate, delivering blow after blow to free and fair elections.

David Wippman is emeritus president of Hamilton College. Glenn C. Altschuler is the Thomas and Dorothy Litwin Emeritus Professor of American Studies at Cornell University.