Last Friday marked the 56th anniversary of President Lyndon B. Johnson’s signing the Voting Rights Act of 1965. This legislation was passed less than five months after “Bloody Sunday,” the attack by Alabama state troopers on John Lewis and other voting rights marchers on the Edmund Pettis Bridge in Selma.

The Voting Rights Act was approved by substantial bipartisan majorities in both houses of Congress, by votes of 328 to 74 in the House and 79 to 18 in the Senate. The only opposition to the Voting Rights Act was from unreconstructed Southern segregationists, almost all of whom were Democrats.

Last week, the U.S. House Subcommittee on Elections commemorated the Voting Rights Act anniversary by issuing a report, “Voting in America: Ensuring Free and Fair Access to the Ballot.” The report demonstrates how, in much of the nation, voting rights is no longer an issue that receives bipartisan support. For many Republican-controlled state legislatures, limiting access to the ballot is an important goal.

This trend comes in the wake of two Supreme Court decisions over the past decade that have substantially limited the reach of the Voting Rights Act. In 2013, a 5-4 majority of the Court ruled that states that were once covered by the Voting Rights Act and required to obtain pre-approval of changes in state election laws and practices from the U.S. Department of Justice were now free to make changes without advance approval. The only legal recourse plaintiffs would have would be to file suit after the changes went into effect.

Earlier this year, a 6-3 majority of the Court made it more difficult for plaintiffs to win such suits, by establishing new guidelines for federal courts to use in evaluating challenges to election law changes. The new guidelines lowered the bar that states defending new election laws against claims of racial discrimination had to clear. In her dissenting opinion, Justice Elena Kagan wrote: “What is tragic here is that the Court has (yet again) rewritten — in order to weaken — a statute that stands as a monument to America’s greatness, and protects against its basest impulses. What is tragic is that the Court has damaged a statute designed to bring about ‘the end of discrimination in voting.’”

The House Elections Subcommittee report noted several areas in which Republican state legislatures and Republican secretaries of state have worked to limit access to the ballot box in recent years. Although purging voters who have died or moved is an important part of maintaining accurate registration lists, states that were once covered by the Voting Rights Act have purged voters at a 40 percent higher rate than the rest of the country. In several of these states, aggressive purge policies based on inaccurate data have disproportionately removed minority voters from registration lists. These purges have often occurred too close to an election to permit voters improperly removed from the rolls to restore their active status.

Prior to 2013, states that wanted to close or consolidate polling places had to receive advance approval if they were covered by the Voting Rights Act. The House subcommittee reported that, since 2016, states have closed polling places at almost double the rate prior to 2016. In southern states with large minority populations, the poll closures have disproportionately occurred in locations with a diverse voting population. Republican legislatures in many of these states are now working to make it more difficult for voters to cast early ballots, or to vote using absentee ballots, thus forcing them into longer lines on election day at fewer polling places.

The Supreme Court’s recent decisions are based on statutory, not constitutional, grounds, so they could be overridden if Congress passes new legislation. The John Lewis Voting Rights Act, which has not yet come to either the House or Senate floor in this Congress, would restore and strengthen those parts of the 1965 act that have been limited by the Supreme Court.

Eric L. Davis is professor emeritus of political science at Middlebury College.