By ADAM LIPTAK

WASHINGTON — The Supreme Court on Thursday evening stopped officials in Wisconsin from requiring voters there to provide photo identification before casting their ballots in the coming election.

Three of the court’s more conservative members dissented, saying they would have allowed officials to require identification.

Around the same time, a federal trial court in Texas struck down that state’s ID law, saying it put a disproportionate burden on minority voters.

The Wisconsin requirement, one of the strictest in the nation, is part of a state law enacted in 2011 but mostly blocked by various courts in the interim. A federal trial judge had blocked it, saying it would “deter or prevent a substantial number of the 300,000-plus registered voters who lack ID from voting” and would disproportionately affect black and Hispanic voters.

The law was provisionally reinstated last month by a unanimous three-judge panel of the federal appeals court in Chicago hours after it heard arguments. The full court was deadlocked, five to five, on a request for a new hearing.

“It is simply impossible, as a matter of common sense and of logistics, that hundreds of thousands of Wisconsin voters will both learn about the need for photo identification and obtain the requisite identification in the next 36 days,” the appeals court judges opposed to the requirement wrote.

The three-judge panel upheld the law on Monday, reasoning that it was similar to one from Indiana that the Supreme Court upheld in 2008.

The challengers to the Wisconsin law asked the Supreme Court to block the voter identification requirement for now, saying it would “virtually guarantee chaos at the polls.” Whatever the legality, they said, the state cannot issue enough IDs and train enough poll workers before the November election.

The law requires absentee voters to submit identification. But forms sent before the appeals court acted did not include that requirement. State officials had said they would not count ballots returned without copies of valid ID.

The officials argued that voters knew of the appeals court’s ruling and that blocking it would cause confusion. “Voters would get the pinball treatment,” they wrote. They told the justices that opponents “legitimately raise issues regarding absentee ballots,” but that local election officials were trying to inform voters that they might have to take more steps for their votes to be counted.

In dissent, Justice Samuel A. Alito Jr., joined by Justices Antonin Scalia and Clarence Thomas, said the timing of the state’s request made it difficult. “It is particularly troubling that absentee ballots have been sent out without any notation that proof of photo identification must be submitted,” he wrote.

But he added that it was not clear that the appeals court had “demonstrably erred” in reinstating the law, as required by Supreme Court precedent to block it.

The Supreme Court’s action was seen as a setback for Gov. Scott Walker, a Republican who, along with a Republican-controlled Legislature, approved the law in 2011. He faces a re-election challenge from Mary Burke, a Democrat.

Critics of voter ID laws say that they disproportionately burden poor, older and minority voters, and that cases of impersonation at the polls are very rare. A recent study by the Government Accountability Office indicated that changes to such laws were behind decreased turnout in some states.

Recent Supreme Court orders have restored voting restrictions in Ohio and North Carolina that appeals courts had blocked. The Ohio case concerned early voting, and the North Carolina case involved same-day registration and votes cast in error at the wrong precinct.

Thursday’s ruling from Texas, issued after a two-week trial in Corpus Christi, found that the state’s voter ID law “creates an unconstitutional burden on the right to vote, has an impermissible discriminatory effect against Hispanics and African-Americans, and was imposed with an unconstitutional discriminatory purpose,” Judge Nelva Gonzales Ramos wrote.

A spokeswoman for the Texas attorney general’s office said it would immediately appeal “to avoid voter confusion in the upcoming election.”

Ryan P. Haygood, a lawyer at the NAACP Legal Defense and Educational Fund, welcomed the decision. “The evidence in this case,” he said, “demonstrated that the law, like its poll-tax ancestor, imposes real costs and unjustified, disparate burdens on the voting rights of more than 600,000 registered Texas voters, a substantial percentage of whom are voters of color.”