A poster at the Alamance Fire Station in Greensboro, N.C., explains North Carolina’s voter ID rules. (Andrew Krech/Associated Press)

Vanita Gupta is head of the Civil Rights Division at the U.S. Department of Justice.

“Now we can go with the full bill.” That was a North Carolina legislator’s promise, just hours after the Supreme Court’s 2013 decision invalidating powerful protections against discriminatory voting rules. Out went the modest proposal. In came a bill designed to shrink the electorate. The legislature passed a law targeting specific practices — including same-day registration and early voting — that had helped drive recent surges in minority voter turnout. The law was aimed directly at the ways that communities of color participated in the electoral process.

It took three years, but on Friday, the U.S. Court of Appeals for the 4th Circuit struck down the North Carolina law. The court wrote that the law “target[s] African Americans with almost surgical precision” and found that, “because of race, the legislature enacted one of the largest restrictions of the franchise in modern North Carolina history.”

Not long ago, we could stop laws like this before they took effect. But the Supreme Court’s 2013 decision in Shelby County v. Holder struck down a core part of the Voting Rights Act. The act used to require jurisdictions with the most troubling histories of discrimination to run new voting rules by the Justice Department or a federal court before those rules could be implemented. Shelby County nullified the way jurisdictions were chosen for this review process, leaving no pre-clearance at all. Discriminatory laws can now take effect without federal clearance.

This problem extends far beyond North Carolina, as Sammie Louise Bates discovered firsthand. She moved to Texas and wanted to vote in her new state, but under the strict requirements of Texas’s voter ID law, she didn’t have the documents she needed. Neither did more than half a million other Texans. Bates — an elderly African American woman — lived on a fixed income of $321 per month, and the birth certificate she needed to get a Texas ID cost $42. As she testified, “I had to put the $42 where it was doing the most good . . . because we couldn’t eat the birth certificate . . . and we couldn’t pay rent with the birth certificate.” Fourteen federal judges — judges appointed by both Democratic and Republican presidents — have agreed that the law violates the Voting Rights Act. But it was only two weeks ago, after a decision by the full 5th Circuit, that Texas was required to break down this barrier.

As North Carolina and Texas highlight, it can take years to litigate these cases. We can challenge the laws in court, but elections don’t stop in the meantime. And it’s much harder to detect subtle local problems in the first place.

For the first time in half a century, the United States will elect a president without the full safeguards of the Voting Rights Act in place. The Supreme Court invited Congress to enact new legislation to address the impact of Shelby County. It is well past time for Congress to take up the invitation to restore the Voting Rights Act to its full strength.

In the meantime, we at the Justice Department will continue to use every tool at our disposal to protect eligible voters wherever and whenever we can. And as recent court decisions demonstrate, we continue to see results. Beyond North Carolina and Texas, in the past week alone, courts have pushed back on voting rules in Louisiana and, pressed by private plaintiffs, in Kansas and Wisconsin , as well. And there has also been progress outside court. Around the country, the Justice Department continues to take action to prevent states from unlawfully purging their voting rolls and to ensure that eligible voters can register and get their ballots with the ease the law guarantees.

Voting transcends partisanship. It makes no difference to the Justice Department which candidate a voter elects or which party he or she supports. We work to protect the integrity of the electoral process so that every eligible voter can cast a ballot. Of course, we need rules to structure the way we vote. But those rules must comply with federal law and treat all voters fairly.

The Founders in Philadelphia, activists at Seneca Falls, N.Y., and marchers in Selma, Ala., all recognized the profound power of the franchise. When we allow discrimination to infect our elections, we disrespect the sacrifices of those who came before us and threaten the progress they achieved. But when we protect the rights of our fellow voters to make their choices, whatever they may be and whomever they may be for, we do our part to build our more perfect union. That means Congress needs to restore the full protections of the Voting Rights Act. State legislatures need to remove unjustified voting rules. Poll workers need to oversee fair elections. And eligible Americans need to vote.

As we celebrate the 51st anniversary of the passage of the Voting Rights Act this week, all of us need to do our part to defend and strengthen our democracy. Self-government doesn’t happen by chance.