The Supreme Court on Thursday upheld two Arizona voting restrictions that a lower court had said discriminated against minority voters, a ruling that suggests that it will be harder to successfully challenge a spate of new laws passed by state legislatures in the aftermath of the 2020 election.

Justice Samuel A. Alito Jr. wrote the opinion in the 6-to-3 ruling, with the court’s conservative majority in charge. The court’s liberals joined an opinion by Justice Elena Kagan protesting that the decision weakens the shield provided by the Voting Rights Act (VRA), first passed in 1965 to forbid laws that result in discrimination based on race.

The final day of the Supreme Court’s decision-making brought a second opinion, about the disclosure of donors, decided along the same conservative-liberal divide. It was a partisan close to a term in which the justices had successfully decided many controversial cases without rancor.

The Supreme Court ruled 6-3 on July 1 that Arizona voting laws can go into effect, despite a lower court finding they disproportionately burden minority voters. (Reuters)

The final day also came and went without word from Justice Stephen G. Breyer about his future; liberal activists and some Democrats have openly called on the 82-year-old to step down so President Biden can nominate a successor while Democrats control the Senate.

Breyer could make such a decision at any time. But it is often at the end of a term when a retiring justice reveals such plans.

The voting rights cases from Arizona marked the first time the court considered how one section of the VRA applies to voting rules that have a disproportionate impact on minority groups. And it came at a time when Republican-led states have adopted a string of voting changes that Democrats say will impose such burdens.

Both supporters and detractors of the decision said that it would probably strengthen the hand of state legislatures that say tighter voting laws are necessary to prevent election fraud and that it would make it more difficult for challengers to eliminate laws that look neutral on the surface but will most impact minorities.

“I am deeply disappointed in today’s decision by the United States Supreme Court that undercuts the Voting Rights Act, and upholds what Justice Kagan called ‘a significant race-based disparity in voting opportunities,’ ” President Biden said in a statement.

“In a span of just eight years, the Court has now done severe damage to two of the most important provisions of the Voting Rights Act of 1965 — a law that took years of struggle and strife to secure.”

Republicans said it was a victory for states and their ability to control and protect voting practices.

“Today is a win for election integrity safeguards in Arizona and across the country,” said Mark Brnovich, the state’s attorney general. “Fair elections are the cornerstone of our republic, and they start with rational laws that protect both the right to vote and the accuracy of the results.”

Liberal election law experts said the decision is part of a pattern that has systematically weakened legal protections for minority voters.

“The conservative Supreme Court has taken away all the major available tools for going after voting restrictions,” said Richard Hasen, an election-law expert at the University of California at Irvine.

He said the court also “makes it harder to prove intentional racial discrimination in passing a voting rule,” which is likely to affect the Biden Justice Department’s complaint about Georgia’s new voting laws.

The Republican National Committee and Democratic National Committee were on opposite sides of the Arizona suits. RNC Chairwoman Ronna McDaniel called the ruling “a resounding victory for election integrity and the rule of law.” She said the court recognized, “in Arizona and across the nation, states know best how to manage their own elections.”

Senate Majority Leader Charles E. Schumer (D-N.Y.) said the decision underscores the need for Congress to enact new voting protections.

“It is difficult to fathom that the U.S. Supreme Court, which is bound by both duty and the Constitution to administer equal justice under law, has done more to set voting rights back than any other actor in the last decade,” he said.

The cases involved two voting regulations from Arizona that are in common use across the country. One throws out the ballots of those who vote in the wrong precinct. The other restricts who may collect ballots cast early for delivery to polling places, a practice then-President Donald Trump denounced as “ballot harvesting.”

Even the Biden administration had concluded that the U.S. Court of Appeals for the 9th Circuit had erred in condemning the Arizona laws. So the outcome was not a surprise.

But the greater impact will be how a section of the VRA — Section 2 — relates to an outpouring of new laws enacted by state legislatures that have changed voting procedures.

That section of the law was amended in 1982 to prohibit any voting practice that “results in a denial or abridgment of the right of any citizen of the United States to vote on account of race or color.”

Chief Justice John G. Roberts Jr. had said Section 2 was in place to protect minority interests after the court in 2013 made it harder for civil rights groups to challenge discriminatory state law changes. Shelby County v. Holder effectively eliminated the requirement that states proved to have discriminated against minorities in the past receive advance approval from a panel of federal judges or the Justice Department before changing their laws.

Section 2 has most often been employed against jurisdictions that rig election lines to dilute minority voters’ impact. But after Shelby County, civil rights groups are using it to challenge restrictions that they say place a heavier burden on minority groups.

Alito wrote that because the effort was new to the court, the majority was not announcing a test to govern all rules “that specify the time, place, or manner for casting ballots.”

The touchstone, he said, was that the rules of voting be “equally open.”

Guidelines, he said, include the size of the burden imposed by a challenged rule; the disparities it imposes on different racial and ethnic groups; and the overall opportunities for voting provided by a state’s entire system for voting.

Also: “One strong and entirely legitimate state interest is the prevention of fraud,” Alito wrote. “Fraud can affect the outcome of a close election, and fraudulent votes dilute the right of citizens to cast ballots that carry appropriate weight. Fraud can also undermine public confidence in the fairness of elections and the perceived legitimacy of the announced outcome.”

Alito was joined by Roberts and Justices Clarence Thomas, Neil M. Gorsuch, Brett M. Kavanaugh and Amy Coney Barrett.

Kagan wrote a stinging dissent, saying the court was undermining the intent of the VRA by weakening the protections in Section 2.

“The majority writes its own set of rules, limiting Section 2 from multiple directions,” wrote Kagan, joined by Breyer and Justice Sonia Sotomayor.

“Wherever it can, the majority gives a cramped reading to broad language. And then it uses that reading to uphold two election laws from Arizona that discriminate against minority voters.”

She added: “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.”

In Arizona, Democrats challenged the two provisions on out-of-precinct voting and ballot collection. A district judge held a trial and upheld them. A panel of the U.S. Court of Appeals for the 9th Circuit agreed with that decision on a 2-to-1 vote.

But a larger panel of the 9th Circuit stepped in and said that the way the provisions were applied in Arizona disproportionately affected Black and Hispanic voters.

Those judges said that the state changed locations of voting places more often in minority communities, leading to voter confusion, and that the rates of discarded out-of-precinct (OOP) votes were far higher in Arizona than in other states. Arizona throws out the entire ballot, even if some races — for governor, for instance — are not affected by the voter’s precinct location.

Democrats said that between 2008 and 2016, Arizona discarded 38,335 OOP ballots in general elections, all of which were cast by registered, eligible voters.

The judges said the ban on collecting ballots was intentionally passed to harm minority voters, who they said were more likely to be homebound or disabled and lacking reliable means to vote in person. Native Americans had in the past been served by community or political leaders who collected early-vote ballots, the court said.

But Alito said the appeals court did not take into account the totality of Arizona’s voting regulations, which include early voting and other accommodations.

It was true, he said, that statistics showed a disparity, but it was not a great one.

“A policy that appears to work for 98% or more of voters to whom it applies — minority and non-minority alike — is unlikely to render a system unequally open,” he wrote.

He said Kagan’s “radical” approach makes Section 2 claims turn “almost entirely on just one circumstance — disparate impact.”

In reply, she said small disparities often make the difference, and that Alito’s approach ignores them. For instance, no court, she said, would approve a system that automatically set aside 1 percent of the Hispanic vote.

She also warned that efforts to diminish minority voting were often wrapped “in election-integrity garb.”

Kagan said some of the new state restrictions “may be lawful under the Voting Rights Act. But chances are that some have the kind of impact the Act was designed to prevent — that they make the political process less open to minority voters than to others.”

The cases are Brnovich v. Democratic National Committee and Arizona Republican Party v. DNC.